Life in Null-Space

Introduction:
This is a 22-page story I have conjured from my erotic fantasies, so be ready for a long read if you want to finish.

Life In Null-Space

Day 1

The spaceship shot through space, its eight engine output cones glowing fiercely, and then it suddenly blinked out of sight; folding space to cross the galaxy in a matter of weeks as opposed to a matter of centuries.

Vera Nomad sat at the helm of the long range skiff and flipped a couple of switches before peering at a glowing screen set into the bulkhead to her right. She nodded her head in satisfaction and unbuckled her momentum arresting belts, and glided out of the pilot’s chair, floating above the floor in the zero gravity. There was gravity in the rest of the ship, but artificial gravity was expensive tech, and was only installed where needed.

The young woman stretched the stress from her limbs; the tight single piece jumpsuit she wore outlining her impeccably trim body. Light from the instrument panels surrounding her silhouetted rather large breasts stretching the fabric enclosing her chest as she pressed her hands to the back of her rib cage and arched her back. She was proud of her titties and the attention they attracted when males and certain females were looking.

Speaking of other females…

The young woman accessed the hatch between the cockpit and the common area of the skiff. The common area consisted of a sitting area with comfortable couches and chairs in the center, and against the walls sat computer consoles and view screens. The egress at the aft end of the room led to the living quarters and maintenance rooms.

Vera had to get her feet underneath her before entering, or risk falling on her face because of the gravity in this section. Her light deck shoes touched the floor and she put her hands on her slim waist, surveying her home for the better part of a year to follow. Deep-Space Surveying was a lucrative business, as not everyone had the constitution to travel through space for upwards of a year to accomplish their objective.

Luckily, Vera and her older sister had such a constitution.

Teresa Nomad actuated the hatch at the aft of the room and stepped through the threshold. Her long brown hair matched her sister’s almost exactly, but Teresa’s eyes were blue, while Vera’s were brown. Vera couldn’t help but check out her sister, who was only four years older than her: Taller by about three centimeters, a bust that almost exactly matched her sister’s, and an ass that stuck out a bit more than Vera’s, causing the men she walked passed to drool.

Teresa smiled at her sister, walked over to a computer readout and checked it before turning and reporting to her pilot.

“Engines are running smoothly, nothing unexpected. Now we just have to be here for ten and a half months.”

“We are on course for Virgo Prime.” Vera reported, “transition was smooth.”

The sisters stared at each other for a moment, the silence growing heavier by the minute. Vera began walking around the couch slowly towards her sister.

“Glad we’re away from Earth and Mars, being around that many people gets exhausting.”

Teresa folded her arms across her breasts and replied, tracking her sister’s movement with her head, “Yeah, people can be so judgmental back there. Out here we can do whatever we want.”

Vera stopped in front of her sister, never breaking eye contact, and Teresa turned to directly face Vera. “About that…”

Teresa smiled coyly and inched a little closer.

Vera leaned closer and up a bit, pressing her lips sensually against Teresa’s mouth. Teresa returned the very non-sisterly kiss, pulling her younger sister into an embrace that mashed their breasts together and allowed their hip bones to touch each other. Their arms wrapped around one another in a passionate embrace.

This job was perfect for the sisters, as they had ten and a half standard months round-trip to play around and frolic to their heart’s desire, with no eyes to frown at their actions.

Teresa took a sharp breath as Vera’s hand found its way somewhere new. Her eyes hooded and glazed with pleasure as Vera rubbed her crotch over the jumpsuit, and her hand eased its way up to entwine in her sister’s hair.

They fell over the back of the couch and tore themselves out of their jumpsuits and underclothes, relishing in being able to touch one another again. Their bodies were so similar, only small differences where there were differences. Their labia and clitoris looked almost exactly alike, the shudder than runs through their muscles upon orgasm were the same, even the little squeak they made when surprised were similar. Both of them had pink nipples that darkened to red when hard and turned on.

Vera detached herself from Teresa’s lips with a sound like a suction cup coming away from a surface, and slowly licked a wet trail down to Teresa’s bare-shaven snatch. She set up shop there, using her tongue and gentle fingers on the labia and vaginal entrance, which pulsed every now and again when Teresa flexed her interior. Teresa’s gentle moans and groans told the story about how properly Vera used her tools.

The younger sibling shifted her rear end, moving it over to straddle Teresa’s shin, and began to grind her mound against the hard shin bone of Teresa’s leg. The burning pleasure that radiated from the contact made Vera blow out her breath and gasp and the building release. Teresa angled her leg so that Vera could use the surface to access every part of her self, so she could build her orgasm how she wanted.

Teresa was soon succumbing to her sister’s ministrations, her breaths and facial expression signaling to her sister that the time was close upon them. Vera paid close attention, making sure to keep her finger movements rhythmic, and when Teresa was vocalizing appropriately, Vera hit her sister’s clitoris just right to send her over the edge. Teresa folded at the waist with wide eyes, her breath held tight in her lungs as the pleasure fell as a torrent, washing through every inch of her tissues.

Vera supported her sister while she peaked, and gently laid her back down, caressing her body with her fingertips. Their breath mingled.

Teresa recovered her senses and grinned, lust still glazing her eyes. She skudded down between her sister’s legs, and used Vera’s ass cheeks as handles to pull her mound down to Teresa’s lips and tongue. Vera held on to the back of the couch with one hand as she closed her eyes, feeling the well within her fill with pleasure until she was sure to bust. Her exhortations echoed around the sizeable room, becoming more and more insistent.

Teresa’s tongue was a hurricane within the first couple inches of her sister’s tunnel entrance, that combined with the pounce of her thumb against her sister’s barely hooded clit, made Vera explode similarly to Teresa’s own release. She sat rigidly, her knuckles white against the couch, her eyes shut tightly and her mouth wide open.

Her body spent for the moment, Vera was laid down slowly by her younger sister, sharing the couch. They both breathed in close to unison while they came back down from cloud nine. When they did, they clutched themselves close to one another in a sisterly embrace, and slowly nodded off together, their hair intertwining and unable to be told apart.

Day 8

Vera’s green eyes scanned the depths of darkness that they moved through. Technically, it was a non-visible plane through which they moved to access different areas of realspace, so there was never anything to see whatsoever outside the viewport. She wore a lose tshirt and nothing else, and tapped a fingernail against the transparent metal that shrouded the small enclosed area accessed by hatchway from the common room module.

Her mind was swirling through possibilities sparked by the understanding of exactly what they were doing. Travelling through space like this meant that they were accessing parts of space otherwise unknown to the human species. It was exciting to her, and would spark her imagination continually throughout the journey, as it had on previous runs.

The hatch slid open and Teresa came up behind Vera, and wrapped her hands around her sister’s midriff.

“I wonder what we will find out there, Rees.” Vera spoke, using her sister’s nickname.

Teresa stared into the blackness as well, a smile tugging at the corners of her mouth.

“It could be anything, little sis. And I can’t wait to get where we are going to break out the survey gear.”

She turned her sister away from the landscape of darkness and peered into her eyes.

“But we have a long way to go. Let’s get to bed, it’s late.”

Vera nodded and accompanied her sister to her sleeping quarters.

During that night cycle, while every light was extinguished and both women were laying in Teresa’s bed sound asleep, an expansive yet sourceless light emitted in the common room. Slowly it coalesced near the aft hatch as a ball of light, returning the rest of the ship to darkness. It flitted about as though curious, but finally slid between the atoms of the titanium-alloy hatch like water through a sieve, and reformed itself in the access hallway. It revolved in place, turned and occupied the open hatchway the led to Vera’s empty bedroom, then turned in place and shot toward Teresa’s closed hatch across the hall and slipped through it as easily as it did the first.

Inside it hovered for a full minute before moving closer to the sleeping forms of the two women lying in repose next to one another. The ball of swirling light descended to touch the arm of one of the forms, and remained there for a long time, until finally it rolled away. Painting an uneven track through the air, the light ball began to shrink until it was the size of a marble.

It drifted closer to the form on the side of the bed nearest the door, slipped under the hem of the loose shirt she was wearing, and occupied the indent in her midriff. As though it was made to sit there, the ball of light swirled within the woman’s bellybutton, until finally sinking down through the base of the indent and disappearing from view beneath the woman’s supple skin.

Neither woman was disturbed for the entire night.

Day 15

Teresa collapsed onto her sister’s chest as their scissoring ran its course to its inevitable end. The orgasm burned inside her, sitting right above where her vagina was located. Both she and Vera beneath her panted as thought they had just run a marathon together, although they had taken turns like usual as opposed to racing.

Their skin was damp from their exertions, and Teresa’s hands shook slightly as they caressed the form of her sister’s body with loving tenderness. Vera shuddered and giggled, leaning up to plant a warm, affectionate kiss against her older sister’s cheek.

“I love you, Rees…” she whispered into her ear.

Teresa gently licked the end of Vera’s nose and repeated the phrase.

“I love you.”

They slowly untangled their limbs from one another and collected their various articles of clothing. The couch had a couple wet spots on its cushions, which the automated cleaning systems would take care of once programmed. The couch in the middle of the common room had become their primary love-making emplacement, as it was center to all shipboard operations, and they were most likely to encounter one another for an impromptu fuck here in the common room module.

Vera dropped her tshirt over her head and it bound up over her sizeable breasts, which stretched and shifted with her bodily movements. She pulled the fabric down over her chest and saw Teresa watching her as she fumbled her way into the shorts she wore in place of panties. Vera looked down and realized that her hard nipples were poking through her shirt, so she pinched them through it, biting her lip against the arc of pleasure through her nerves.

They parted without too much more play, as they had just spent the last couple hours pleasuring each other fully. Soon it would be rest period, as indicated by the digital clock set to standard time in the Sol planetary system. Teresa went to a control station against the bulkhead and began programming the cleaning system to erase the mess they made on the couch.

Vera decided to take a shower before she settled into the cockpit for her customary guidance systems check before bed.

In an alcove just off her bedroom, Vera threw off the shirt she had worn and hit the button to allocate and warm some water for a shower. Her orgasmic pleasure still glowed in the pit of her stomach, which was out of the ordinary, but she wasn’t alarmed. She caressed her tight belly between her belly button and where her nethers began with one hand, and cradled one breast with her other hand, examining herself in the mirror set into one wall. She came to the conclusion that she looked just as perfect as she always did.

I’m so lucky to have such a relationship with my sister. I just feel so fulfilled!

She let go of herself and activated the water, stepping under the warm stream. After cleaning herself, she shut the water off and began the dry-off sequence.

Something shifted inside her.

She stopped all movement. She noticed that the warmth in her belly that had been ignited after the orgasm she just got from Teresa was still there, and in fact had not decreased in the slightest. It was from the midst of that warmth that the movement happened.

It happened again, with no attendant pain. In fact it was a slightly pleasurable sensation, if completely alien to her.

Vera felt it again, only insistent this time. She gasped in fear as it was felt up near the end of her vaginal canal, where the unused uterus sat above the cervix which connected the two. She examined the skin below her belly button, felt it with her hands, and when the next insistent movement happened, she felt a swirl beneath her hands. She gasped in complete shock. It reminded her of what it felt like when she had felt her friend Andrea’s pregnant belly a few years ago and felt the unborn child turn in its sleep.

But Vera knew for a fact she wasn’t pregnant, as she had never had sex with a man. And even if she was, it wouldn’t explain what was happening to her.

All at once, she felt a sliding, churning feeling inside her midsection. Vera, breathing heavily, sank to the floor of the shower, feeling everything that was happening inside her belly with her hands. It was if her guts were shifting around.

“Teresa! Come here quick!”

As she called her sister, she distinctly felt pressure on her cervix area, the deepest part of her vagina. Her eyes widened as she felt the urgent need to push with her kegel muscles. So she did.

Teresa burst into the shower alcove to find Vera sitting in the now-dry shower with her legs spread wide, her hands clutching her lower midsection.

“Rees, Rees, something’s happening to me down there. It’s really weird. Like there’s something inside-”

She ceased speaking and instead took a breath and grunted with effort. Teresa’s gaze turned to her sister’s vaginal opening, and saw it clench with sympathy with Vera’s efforts. She couldn’t be sure, but she thought she saw her sister’s clitoris receding deeper into its hood, and her vagina lips become less pronounced. She could find no way to voice these observations, as the event was so weird, so completely unexpected that she was frozen, staring at her sister’s crotch.

Vera groaned with insistence and bent over her own midsection, squeezing her eyes shut.

The head of a penis popped out of the entrance of Vera’s vagina, followed immediately by a shaft. Teresa’s gasp of sheer surprise was drowned out by Vera catching her breath for another push. Following that, a scrotum filled with a pair of testicles dropped out beneath the shaft.

It was suddenly over. Teresa could see that where her sister once possessed a beautiful female sex organ, a bulky set of male genitalia now hung from her crotch.

Vera panted with relief as the need to push stopped. She felt like there was somehow less than there once was beneath her searching hands, but other than that, she felt fine again, if a bit out of breath. Her eyes returned to her sister, who stood in the doorway.

“That was insanely weird.” She stated rhetorically, but her lightening mood halted as she saw her sister staring with shock at Vera’s vagina.

Vera frowned and looked down at herself, and almost shrieked in surprise. She didn’t have a vagina any longer! She now had what looked like a full set of sizeable male equipment. Vera reached out and tentatively touched her brand new penis, which was soft and wet. At the touch she involuntary flinched, and the penis flopped over to lie against the other leg. She reached further and grasped the set of testicles she now sported.

With wide eyes, she looked up at her sister. “What-?”

Teresa looked just as shocked as her.

Vera managed to get up off the floor and stood a bit spread-legged to allow room for her new appendages.

“Are you ok, Vera?”

Vera wondered that herself. She felt fine, like she didn’t feel weak or sick or anything. The only thing she could find wrong with herself was the fact that she had a fucking cock and balls hanging from where her vag should have opened. She felt around with her hands; there was absolutely no vestige of a clit or lips or anything.

Vera blew her breath out through her mouth and ran her hands through her hair.

“Let’s go into the common room so we can look at you, ok Vera?”

Following Teresa’s suggestion, they proceeded to the now-clean couch where Vera sat down with wide knees; she had noticed that the testicles were rather sensitive. She turned the penis this way and that, trying to rationalize in her mind what her eyes were seeing.

Teresa went over to a panel and tapped a sequence of buttons. A scanner descended from the ceiling and made a couple of loops around Vera’s body, then retreated into where it was enclosed in the ceiling bulkhead.

“Readings are coming in, Vera. Don’t worry, ok?”

Vera smiled bemusedly at Teresa’s placation. Don’t worry about what? Turning into a man?

Teresa read the screen carefully, not wanting to misread anything.

At all of this physical stimulation, Vera began to notice that the cock she now wore began to swell and lengthen. She let it alone, feeling the muscles at the base of the penis becoming hard, and tried to concentrate on something else. She stared out the nearest viewport, trying to penetrate the blackness without, when an idea struck her.

“Rees! What if this is an alien influence?”

Teresa turned in her chair and cocked an eyebrow at her younger sister. “Alien influence?”

“Yeah! What if an alien came and…”

Her thought trailed off when she realized how dumb she sounded. Why would an alien have something alien to it grow a different set of genitals?

“Forget I said anything.”

Teresa got up from her chair and sat down on the couch next to her naked sister. “It may not make sense, but honestly, it’s a better theory than I have right now, since I don’t have a theory. The body-scan painted you as in great health, with no aberrations except for the fact that you have male sex organs, and a bit more testosterone rather than estrogen going through your system. It’s as though you always had these organs, and will always have them.”

Vera shook her head in confusion and exasperation, staring at the sizeable meat protruding from her crotch.

Teresa felt her sister’s confusion, and wanted to help her somehow. “At least you still have these!”

Teresa’s hand gently grasped Vera’s right breasts and kneaded it. Vera drew in a breath and met her sister’s eyes with love. I’m seriously blessed to have a sister like her.

“Yeah, I’m still mostly woman. I hope that’s enough for you…”

Teresa leaned over further and their lips met, and danced around each other’s tongue. For a moment, Vera was again lost in the pleasurable haze of the last fortnight, running her fingertips along her sister’s rib cage. She broke the contact with her sister and grinned at her.

She jumped a little bit when she noticed the cock between her legs had swollen to more than twice its flaccid size, easily reaching seven inches long and with a radius of at least an inch. It had happened unbeknownst to her, but she could feel her blood pulsing through it, and the hardened muscle flexed at her command; moving up and down in her lap. Her hips were still wide and shapely, but the cock sitting there looked so… alien to her.

Strangely though it’s not completely unattractive…

Teresa sat back and pointed at the member pulsing in her sister’s lap. “I don’t know how I’m going to get used to that.”

Vera looked back at herself and frowned in thought. Both she and Teresa were lesbians, and had always been so, neither one of them having ever had sex with a man. Men had never interested them before, not even when they had experimented with dildos and the like. Now, however, they had to consider a whole new perspective on lovemaking.

As she looked back at her sister, Vera realized that it was that: love. This was the love between sisters, something unique in its own way. She didn’t think that the difference in organs would diminish the love that she and Teresa shared, but she was scared of that possibility.

Their eyes met, and Teresa spoke first.

“Let me sleep on it, ok? There’s just too much to absorb at the moment.”

Vera nodded with understanding, and gingerly got to her feet.

“I think I have a skirt around here somewhere; skinny jeans just aren’t going to cut it.”

Teresa snickered before she could stop herself, and slapped a hand to her mouth. They shared a meaningful glance again before the older sister got up and left the room with a wink. Vera, staring at her sister’s swivel-hips until the last moment they were visible, found her skirt and put it on, being careful around the new goods she was packing.

She cocked her head at her penis: it was already softening and shrinking back to its manageable size. Within a few minutes, it was barely a bulge at the front of her light skirt.

So this is what it’s like to be a guy. Hmm. Not bad.

Teresa switched the lights off in her room and crawled under the sheer sheet and lay back into the pillows.

This was one wild day. The only woman she had ever loved now has a penis. It just doesn’t make any sense.

At one point she was thoroughly disgusted by men and cocks and semen, but in recent years she had cooled off about it since she hadn’t really tried to relieve her ignorance on the subject. She officially considered herself not interested in men after she and her sister had begun secretly seeing each other.

This was a completely unexpected turn in their relationship though, and she wasn’t quite sure how it would be affected.

It wasn’t like it was revolting anymore, having a penis penetrate a vagina, in fact it was completely natural. It was how things originally worked before the modern development of sexual fetishes.

Plus there is a large dick growing off of where my mouth just was earlier today. My sister.

Teresa shifted her legs in bed, allowing a little fresh air to touch her nether regions. She was genuinely surprised to be turned on at the prospect of her sister’s change.

I’ve never really thought about taking a dick. It could be hot. I’ll see how I feel in the morning.

Alone in the cockpit, Vera was very conscious of the bulk between her thighs as she sat strapped into the pilot’s chair and ran the computer through its nightly paces. The fifteen minute routine was just to verify that they were properly transitioning planes, and she blew through it no problem.

Now it was just her and the elephant in the room.

She had decided that since she was stuck with a penis, she was going to explore what it feels like; Vera was always a very sexual person.

Clicking free of her seat restraints, Vera gently floated upward while losing her clothing. She sighed and prepared herself for what had grown down out of her insides to replace what she already had.

In the zero-gravity, her junk hung free.

She used her fingers to caress and squeeze her shaft, enticing it to harden, and soon felt the tightening of her muscles at the base of her penis. The head rose out of the foreskin’s embrace and the shaft became hard, so erotically hard…

She noted that she was sweating, and her breaths came faster than normal; she was really into this.

With one hand she grasped her now-hard cock in her dominant hand, and came up with her left to pinch a nipple, causing her nerves to zing. She gasped and began to move her fist up and down the length of her member, like the stories she had heard had went.

A little dollop of clear viscous fluid slipped from the end of her cock and floated in the air before her face. She caught it with her fingers and brought it to her mouth, sucking it off her fingertips.

Mmm, pre-cum tastes good!

She licked her lips and resumed the motions, feeling how she alternated flexing and not flexing her nether muscles made the motions work on her. Working toward an orgasm this way was very different than the old way. It felt hot, holding a rod of meat that was connected to her, and feeling her balls tighten up close to her body and then hang down in time with her muscle flexions.

Her thoughts turned to her older sister in bed, and how it would be if she came around to this change. She thought about Teresa’s gentle caress, and about plunging this new cock into the depths of her womanhood. Her hand worked herself more and more rapidly.

Unexpectedly, she felt a rushing in her bowels, and her testicles drew up tight against the base of her straining cock. Pleasure built in her abdomen and spread to all parts of her body; her mouth opened in surprise and sheer primal pleasure as her hips bucked forward toward the ceiling.

A strand of gossamer semen shot from the end of her cock, its speed of ejaculation aided by the pre-cum, and went until it splashed against the metal bulkhead that comprised the ceiling of the cockpit. Her eyes squeezed shut and shot back open as and other pulse of hot cum escaped her new appendage and arrowed through the zero-g environment. Two more silvery ropes followed, of decreasing size and length, each sticking to the bulkhead in various places.

Vera panted, overcome by a release of a dense cloud of pleasure that she had to fight through to regain her wits. She blinked slowly and let her clenched hand relax and float free of her cock, still pulsing intermittently, but already slowly shrinking. The woman sighed in contentment; her fingers and toes tingled.

Floating in the cockpit of her spaceship, naked, Vera Nomad drifted off to sleep.

Day 16

Teresa woke, and noticed that Vera was not in bed with her. She sighed, remembering the reason.

She stretched and got out of the bed, shirking her nightclothes. Her tits pulled up with her arms as she clasped her hands over her head and yawned away the sleep. Toes curled and kneaded the carpeting.

A pair of panties and a jumpsuit later, and Teresa was tying back her hair and exiting the room. The door to Vera’s room was open and the light on as it was the night before.

Strange. Where is she?

The young woman slid the door to the common room open and found it lit at the evening lighting level; just like it had been the previous night. Her pace increased the closer she got to the pilot’s hatch, slamming herself to a stop at the portal window. She stared through and gasped at what she saw.

Vera was floating alongside a bank of computer consoles, completely naked. Teresa frantically actuated the hatch mechanism, but realized before she entered the room that Vera was indeed still alive; she could see the gentle movement of her sister’s rib cage inhaling and exhaling.

As soon as the hatch ponderously began opening, Teresa shouted in at her little sister, calling her name. Vera’s eyes snapped open and she looked around.

“I’m okay, Rees. I must’ve fallen asleep up here!” Realizing she was still naked, she swiped at the nearest article of clothing, and swam through the air to get the other. She twisted deftly in the air and found purchase with her feet, now completely upside down relative to the rest of the ship, and slipped her shirt on over her head. Her hair bloomed through the opening, radiating out around her head as she situated her shirt, then it swooped down after her head as she bent down to pull her skirt up over herself.

Teresa couldn’t help but stare at her lover’s new genitals the entire time. The balls in their little sack drifted around with the cock, swaying in midair, and slowly engorging, despite nothing overtly sexual transpiring at this time.

Vera finished dressing herself, and floated down with a sheepish grin on her face.

“Sorry Rees, I was, um, experimenting after my nightly checklist and I guess I got carried away.”

The younger of the two pointed behind her up to the ceiling, where Teresa saw four off-white splotches dried against the metal. She laughed and hugged her sister close, the fear of not knowing where Vera was at was wearing off and relief flooded in. They hugged each other for a minute, Vera still floating in the null-g cockpit; her skirt flaring out away from her body and her hair standing up every which way, while Teresa still stood on gravity-charged floor plating, allowing her clothes and hair to lay naturally.

Teresa unconsciously broke the embrace when she felt a shifting between her legs; between her sisters’ legs. Vera floated back against the pilot’s seat, her cock fully hard again and pointing straight at Teresa’s face, the skirt not doing a single thing to hide it, even if she were to step into gravity. Vera wrapped her arms backward around the seat back, and allowed her clothing and cock to float as they would. “I have a surveying job for you, Miss Nomad. There’s some… …topography down south that has changed recently…”

Her coy smile and lighted eyes made Teresa smile wholeheartedly. As long as Vera was still the same old Vera on the inside, Teresa could get used to any outside changes, she was sure now.

Teresa slowly shirked her jumpsuit and left it in the common room. A half step forward provided her with enough inertia to drift forward with her arms out, grab the top of the seat back behind Vera, and press her lips against her lover’s mouth, each closing their eyes and sinking into the rapture of kissing the person they love. Teresa pressed forward to hold her body against Vera’s, but a rather large muscle lay between their bellies, preventing them from pressing their hip bones together like they used to. Vera reached down with one hand and pressed her rigid cock down to slip between her sister’s thighs; its tip emerging beneath her pale butt cheeks. Teresa giggled around a gasping breath as they came up for air.

Brown eyes blinked languidly, their long lashes batting at Teresa. Vera stretched her arms above her head and allowed her older sister to guide the floating shirt up and off to float around the ceiling somewhere. Her beautiful breasts freed, Vera gestured Teresa back close and embraced again, their very similar breasts mashing against each other, and their legs wrapping around each other’s like space tentacles. Vera loved just being here, as close as she could possibly be to her lover, almost one with her flesh.

Wait- I can be even closer, now that part of me can be stuck inside her!

The thought gave Vera a thrill, and her cock, still enclosed by Teresa’s thighs, pulsed and jumped a bit. Teresa giggled breathily and gripped the member between her strong thighs, and slowly bucked her hips so that the cock rubbed against her panty-clad pussy, giving them both a thrill.

Vera stared into her sister lover’s blue eyes and pushed her back off of her. With a bitten off shriek from Teresa, Vera gripped her sister by the shoulder and hip and spun her around their z-axis, bringing her crotch to about chin-level.

“Still getting used to this zero-gravity business,” Teresa giggled, “and now your monster alien cock is staring me in the face!”

Vera chuckled and worked the panties off of her sister, flinging them free in some arbitrary direction. Her legs slowly spread, granting the beautiful vision of the pussy lips spreading apart and showing her cave and her hooded pearl. She glanced down before diving in.

“Take your time, sis; I know it’s completely unfamiliar to you.”

Teresa nodded, but bravely gripped her sister’s hip with one hand and grasped the muscular cock in the other. She felt along every inch of it, feeling every vein between the head and base, and gently massaging the testicles in their scrotum. She sniffed it and found it to have its own distinct smell, which still smelled like sex, but different, heavier than the scent of her sister.

Vera was still getting used to the fact that she had a cock, and it was now in her lover’s grasp. She was vibrantly excited though, to do something different than take the same old beaten paths to an orgasm; now there was an unknown thrown into the mix again, spicing up the sibling’s relationship. She licked her lips and dove in at Teresa’s snatch.

As she used her fist to hang on to the loose skin and jack it up and down the shaft, Teresa gasped and froze as her sister planted her open mouth on Teresa’s open vagina, and diddle her clit with her tongue. Her breaths came irregularly; every tongue motion on Vera’s end provided different levels of pleasure at different moments. It made it hard to breath consistently with random spikes of electricity arcing through her body, or so it seemed.

The older sibling brought herself back to the moment and stared her sister’s dick in the eye. She decided to go for broke, and wrapped her lips around the base of the head, sucking on it and allowing her tongue to circle the opening at the end.

“Oooooh…” came Vera’s response.

Little tidbits of memory came back to Teresa, especially from her secondary school days when she and all her girlfriends were exploring, some with boys, but her own self only with other girls. However, she still remembered the rumors spread about how sex worked between a boy and a girl.

She drew back and the head popped out between her lips with a smack. She licked her lips again and put her mouth around it again, taking another inch or so past the head into her mouth this time, and then another inch. It was brushing the back of her mouth now, where the roof of her mouth curved down to form the uvula.

Just as I thought. I can finally put this lack of gag reflex to good use!

Remembered her friend when she was younger, Kathy, telling the other giggly girls at a slumber party that the trick to fitting every inch of cock in your mouth and down your throat was to not breathe, and to pretend like you’re swallowing the dick, using the same muscles as swallowing because otherwise it might go down your windpipe.

So, she drew back again, clearing her throat and taking deep breaths in preparation. Sparks still flew from where Vera was using her tongue against Teresa’s womanhood, but it had dialed back a bit while she concentrated on feeling what giving a blowjob felt like.

Time to surprise her.

Teresa took a lungful of air, and lowered her head down onto her sister’s cock, and almost immediately felt it push against the back of her throat. Angling her head back, she pushed it back further, feeling the head slip down her throat.

She heard a gasp vaguely come from her crotch area.

Halfway there.

Teresa let go of the member and used her swallow flexion to aid the passage of the thick meat over her tongue and down into her esophagus. With another adjustment to her approach angle, the young woman simultaneously pushed her face down into Vera’s scrotum, while feeling her neck expand to allow the large intruder in her throat. The penis down her throat was throbbing hard; she relished the feeling of two heartbeats resounding within her. She closed her lips around the absolute base of Vera’s cock and reveled in her triumph. She could feel her chin pressing against Vera’s pubic bone.

“Oh God—Rees that’s—I’m gonna—“

Gripping Vera’s buttocks in both hands, Teresa braced herself for the explosion she was sure to come; noticing Vera’s balls drawing up close to the base of her cock, where Teresa’s lips were still encircled.

Vera shivered and groaned, and then her hips bucked, pushing her pulsing cock a half-inch deeper down her sister’s throat, into which shot a stream of semen. Teresa wasn’t prepared for how warm it was, but she sucked as best she could, attempting to pull the cum out of her sister as much as it was ejaculated. Vera’s next groan was high-pitched and shocked as the negative pressure sucked the mixing fluids out of her, adding immensely to her pleasure. Three more times Vera’s hips pushed her cock deeper into Teresa’s esophagus, filling her stomach with warm seed.

Need air!

She properly angled her throat so that she wouldn’t hurt either one of them, and pulled the drained cock out of her neck a couple inches at a time; a moan escaping Vera’s lips, somewhere out of sight above her. As the head of it cleared the back of her throat, she blew out the breath around the cock and took a few deep breaths before using her lips and tongue to clean all the cum off of Vera’s sensitive dick.

They slowly drifted apart, Vera coming up short against the back of the pilot’s chair. Teresa was still breathing hard and licking her lips, very conscious of the glow in her stomach from the deposit Vera had just made there. The taste of her sister’s cum was heady and strong, and lingered in her nose. Their eyes met.

“That. Was. Amazing.” Vera remarked, still high on pleasure and gripping the seat behind her as her dick shrunk back down to regular size.

Teresa gripped the hatch frame behind her as she caught her breath. “I wasn’t actually sure if that was possible or not. I had heard things, of course. But now I got to try it, and it was extremely hot.”

“I’ll say. This turned out to be one of the best unexplainable things to happen to me!”

“To us.” Teresa corrected with an evil smile.

Vera pushed off her chair and drifted toward her lover, and they embraced, mashing their breasts together as they shared a heartfelt hug.

Day 18

Teresa sighed and replaced the bookmark in her book. She just couldn’t concentrate.

She knew that Vera was up in the cockpit, reading her own book, as the constant presence of someone for days on end can get old. As a result, whenever the sisters didn’t have a job to do together, and whenever they weren’t entwined in the sweet throes of passion, they were about as far away from one another as the confines of the spaceship allowed.

In her alone time for the past few days, Teresa had been pondering on the differences between heterosexual intercourse and homosexual intercourse. She had come to the conclusion that there really wasn’t too much of a difference despite the physical disparity, which is what she was attempting to come to grips with. Sure, she had deep-throated her sister’s monstrous new addition, and it was extremely erotic on many layers to both individuals, plus it was breaking new ground for Teresa, who had never once even seen let alone touched a penis in real life. But the next step was huge.

Teresa knew that Vera wanted to penetrate her to her very depths with her new cock, and that was different than a dildo or a pair of fingers. She had decided a few times during her recent ponderings that she was going to, and that it was incredibly hot, but they just hadn’t yet. Teresa was inexplicably reserved.

It reminded her of just before she made love to her first girlfriend, just after high school. The act was so socially taboo that she could barely do it. But, she had found that she just had to go for it, to hell with the ramifications, because she emotionally wanted it so badly that it was worth any potential fallout.

There though, there was very little potential fallout.

Throwing her book across the room and getting off her bed, Teresa resolved to go in there and try a new thing.

She actuated the hatch, and as it slid sideways, saw her sister Vera floating in the air sideways, her brow furrowed and a thumbnail in between her teeth as she read her novel. Her hair flooded around her head, restrained enough by a ponytail that it wouldn’t inhibit her reading.

Vera looked up at the door opening. “Rees! What’s up, need help with something?”

Teresa stepped into the zero-g and used the handholds between the consoles to climb her way to where Vera floated. She fixed her sister with a stare that said she had come to a decision.

“I’m ready for you. Let’s do it.”

At Teresa’s exhortation, Vera’s eyes lit up, and she tossed her novel behind her. A twitch came from the folds of her skirt, belying exactly how she felt about the idea.

Teresa smiled and braced her foot against a handle, using her hands to gently push her sister back against the transparent viewport. They shared a kiss, a very non-sisterly kiss, at the end of which made Vera grin.

“I’m so happy you want this, Rees. I was afraid that we…”

Teresa put her hand over her lover’s mouth, snaked her other hand up under Vera’s shirt, and grabbed a fistful of boob. The breath hissed through Vera’s nose as her nipple was tweaked, and fire rose in her eyes. She reached down and pushed her skirt down, kicking it away with her foot, and began massaging her cock, almost fully hard by this point.

Vera pushed her sister’s hand away from her mouth, and prompted her down towards the piece of meat pushing at Teresa’s belly. Teresa eagerly descended and stabilized herself by holding on to Vera’s hips, the gentle outlines of which were slightly silhouetted by starlight, and which sent a thrill through Teresa’s chest and stomach. She threw herself on Vera’s cock with a moan of released anticipation.

First she licked the head and shaft, then planted kisses on the head, finally taking a few inches into her mouth. A sigh came from Vera, drawn out and spastic as Teresa began bobbing her head up and down, a slurping sound coming from where her mouth lost pressurization between her lips and the shaft of the penis. She could feel it throbbing, and whenever Vera flexed, she felt the head of it grow inside her mouth.

The dick disappeared down Teresa’s throat in one fell swoop, eliciting a surprised “Haa…” from Vera. Teresa looked up into her sister’s eyes with her cock in her mouth, and withdrew inch by inch, popping the head of the cock from her mouth. She grinned.

“I’m only going to do that once this time, since you came so fast last time.”

Vera nodded and pulled her up to eye level again with one hand, using her other to tear at Teresa’s shorts until they were pushed down and kicked away. She then reached out and touched Teresa’s vagina lips, slipping a finger down over the sheathing of her clit, and touching the edge of her entrance; it was already very wet.

Breathing harder than normal, Teresa reached behind her and found purchase with her off hand against the face of a computer, and planted her feet against the glass of the viewport on either side of Vera’s hips, preparing for penetration. Using her leverage, she whooshed out a breath, and slowly descended, Vera gripping her dick by the base and lining it up with Teresa’s lubricated vagina.

The head of her cock, oozing pre-cum, pressed against Teresa’s nether regions, making her gasp and flinch a bit at the contact, despite her anticipating it. She grinned sheepishly at the reaction.

She angled her pelvis such that her opening allowed the cock access, and descended upon it. The head felt larger than she thought, causing her to bite her lip and moan, but it entered with no trouble. She pushed down further, feeling it slide along within her innards, along a path never trodden by flesh. Halfway in, she paused and blew out her breath, not realizing she had been holding it, and backed off a bit.

Teresa pushed down again, and this time pushed it in as far as it would go. Vera gutturally moaned at the sensation of part of her being completely enveloped by her lover’s vagina, and she gripped Teresa’s thighs as she continued. Teresa bottomed out a half inch shy of complete burial of the organ, so she backed up and sighed, just reveling in the feeling of a throbbing cock being up inside her lower belly.

She was so glad she decided to do this.

Vera’s eyes were just as wide as her sisters, as both of them were sharing this new experience. Teresa started to move again, but Vera grabbed her by the legs and shook her head.

“I’m so close right now, let’s just wait for a minute, ok?”

Teresa smiled and nodded and held herself in place, needing a moment to adjust anyway. She reached out and ran a hand through her sister’s floating hair.

“I don’t know why I never tried this before, its so awesome. It feels like you’re filling a space inside me that has always been empty!”

Vera laughed, “You’re so tight I feel like I’m going to lose circulation in my cock.”

Teresa giggled, and wiggled her hips. Vera exhaled quickly, but she realized that she wasn’t as close anymore, so she pushed her hips up, feeling the head of her cock push against the end of Teresa’s vagina. Teresa bit her lip and flipped her hair out of the way, using her hips to slide Vera in and out of her barely an inch. Vera pushed her hips up to meet every advancement, and they soon found themselves fucking with abandon; each woman emitting squeaks and groans and little yells as they each hit each other’s most sensitive spots.

Leaning forward so that their tits touched, Teresa dug her teeth into Vera’s neck, while Vera grabbed a double handful of voluptuous ass cheek. She thrusted up into her sister as quickly as she could despite her inexperience with her current equipment, and when she began to play with Teresa’s clitoris, it was only a matter of time until climax.

Teresa began to breathe more and more quickly, until she arched her back and shrieked at the hatchway above them, her orgasm shuddering through her body, making her toes curl and her fingers clench for many seconds. Such a thrill flew through Vera at the realization that her cock had made Teresa cum; she felt a shift in her guts and a rushing feeling in her balls, a bloom of pleasure reaching through her being.

“Gods above, I’m- I’m gonna-“

Before she could finish her sentence, Vera’s hips bucked forward as far as they would go, her pulsing dick pushing all the way into Teresa’s snatch; their pelvic bones pressing against each other.

Teresa felt what could only be described as a splash near the end of where Vera’s cock was shoved into her. In an instant, the thought of an unplanned pregnancy spiked through the haze of her orgasm, and she immediately pushed off the viewport, floating away from her sister.

Vera, lost in her climax, hardly felt Teresa slide up off of her slick dick, but bucked her hips again, causing a healthy stream of semen to explode from her purple cock head and follow her sister across the room.

As her back hit the bulkhead, Teresa stabilized herself and looked down at Vera, just in time to see the stream of cum spearing toward her, but before she could move out of its way, it ended its vector by sliding perfectly in between Teresa’s pussy lips and up her gaping vagina. Teresa had moved away from Vera in an exact line from where they had been connected, so Vera’s unconscious aim was perfect.

She gasped at the entrance of the semen, frozen in place and staring down at herself, wondering at the incalculable odds of that happening. As she watched her pussy twitch, a second airborne stream of man-cum shot from her sister and followed the other one, disappearing up her snatch, leaving only a bit behind to cling to the lips.

She decided to move before that could happen again, so she angled herself to catch the next bursts in her mouth. Two more pearly shots of fluid of decreasing size emerged from Vera, crossed the room, and landed on Teresa’s tongue. She closed her mouth around them and swished it through her mouth, reveling in the heady flavor.

Vera looked up to see Teresa stick out her tongue with cum on it, then close her mouth and swallow so that she saw. She then floated back to Vera’s embrace, both of them breathing heavily, the tendrils of their respective orgasms still clutching their souls.

“You shot your man-cum inside me, Veer. What if I…”

Vera held Teresa so that she could look into her eyes. The pleasure was wearing down, and realization of exactly what had happened was beginning to play across her features. She began to look uncertain, scared, and most of all, guilty.

“I- I’m so sorry Rees, I wasn’t even thinking. I’ve never had to worry about where I came before; I’ve never had sperm before!”

Teresa bit her lip, the taste of fresh cum on her lips still, and frowned, before lighting up with an idea.

“Birth control! We can program the converter module to put together the proper chemicals for a birth control regimen!”

Vera grinned at the idea. “Perfect!”

Teresa planted kisses over her sister’s face in between words, “And then- you can- fill me up- whenever- you- want.”

Her lips finally found Vera’s, and they reveled in their embrace.

Day 49

Teresa Nomad held on to the headboard of her bed and squeezed her eyes shut, holding her breath as her Vera slammed into her pussy with increasing speed. Teresa’s orgasm roiled and built with every swirl of her hand around her clitoris and every rapid thrust from her sister’s cock, until finally she exploded.

She yelled at the heavens and curled her toes, feeling Vera’s cock slamming up against her cervix over and over again.

Vera took shorter and faster breaths until plunging inside Teresa as far as she could and emptying her balls into the depths of her older sister. Vera moaned in sequence with her bursts of semen, and when she was done, she all but collapsed onto her sister’s chest; mashing their breasts together. Teresa let go of the head board and wrapped her arms around her sister’s sweaty back and just focused on breathing and being underneath the love of her life.

Every night for more than a month they had made passionate love, and once in a while during the day, too. With this newfound chemistry, it’s as though it was a brand new relationship, with all the ardor of their earliest years together, and both girls had all but forgotten the mysterious circumstances that led to their newfound love.

Vera got to her knees and eased herself out of Teresa, both girls humming in sequence at the final stimulation of their respective sex organs, until the head of Vera’s cock popped out of Teresa’s vagina. Some man-cum leaked out after it, but Vera caught it with her hand and licked it off her fingers. She loved the taste of her own cum even more now that it was semen, as opposed to vaginal secretions.

Teresa giggled and reached down herself with her hand, swiping with a couple fingers inside her vagina, trying to get a gob of her lover’s cum to suck off her hand, but she came up empty every time. She shrugged, pecked her sister on the lips, and energetically rolled off the bed and strode toward the shower. Morning sex was rare, but today, not worn out by the previous evening’s exertions, Teresa was content to get her brains fucked out by a now exhausted Vera.

As Vera recovered, Teresa washed herself, smiling up into the falling water. Clean, she shut off the water and began to dry herself, but caught sight of herself in the full-length mirror. She ran her hand up over her belly, noting the addition of a couple inches around her waistline.

Going to have to spend more time exercising from now on.

She frowned at herself, then dried her hair and went out to rejoin her sister, who was still lying on the bed. Teresa jumped up on the bed with a grin on her face and straddled her sister.

“You better go take a shower, Veer. I’ll be needing that cock clean by tonight.”

Vera smirked and pushed herself up on her elbows.

“Look at you, a month after converting to bi and you’re happy as a clam.”

With a shrug, Teresa leaned down and bit at her sister’s earlobe until Vera squealed and pushed her off of her. Her boobs jiggled as she got up and stumbled into the shower alcove and started the water.

Vera was getting used to the bulk between her legs; it really wasn’t that great of an intrusion, although it made it extremely hard to hide when she was aroused. Not that she really needed to. She scrubbed and rinsed, and then spent a moment staring at her body in the mirror as she toweled herself off. It was still something she was trying to get used to; having a pair of decent sized tits, but with a long cock and a scrotum hanging from her crotch. It was weird, but erotically so, and she was sure she could get used to it.

A smile settled on her lips as she got dressed and ordered her hair. When she finished, she returned to the bedroom where her sister waited, and together they went out to the common room, ready for a full day of experiments and calculations.

A battery of tests that took all afternoon had revealed nothing about the space through which they traveled, which left them with what earth-based scientists already knew. It was disappointing to Vera, as a breakthrough scientific discovery would be crucial to understanding more about the space in this null-plane, and exactly how the technology worked that let them access it.

After completing the notations on her last experiment of the day, Vera filed her papers and shut down the computer she was working at. Her mind still occupied with calculations and probabilities, she took a portable tablet with her to the couch and nibbled at something to eat.

After about a half hour, she shut down the plate computer and looked around the room. Teresa was nowhere to be seen. Vera set the tablet aside and got up, her dick swinging and slapping against her legs beneath her skirt. Proceeding to Teresa’s bedroom, she found her sister in a daze, staring at something in her hand. She looked up at Vera’s query.

“I’m pregnant.”

Vera stopped in her tracks so quickly that she almost fell on her face.

Pregnant??

“But… But the birth control?”

Teresa tossed the pregnancy test aside and sighed, her hair falling over her shoulder as she turned away from her sister. Vera immediately came forward and sat on the bed next her and pulled Teresa close, wrapping her arms around her middle. For a moment they just sat there, rocking gently. After a while, Teresa broke the silence.

“Will you still love me? Will you still be with me?”

Vera recoiled a little, enough to look her lover in the eyes.

“Of course, Rees. I will help you raise this child. After all, I put it there. Seems only right.”

Teresa seemed surprised by Vera’s response; shocked would be more accurate.

“Really?”

Vera grinned and laid a hand gently on Teresa’s midsection, which held her child.

Teresa threw herself against Vera, their lips meeting roughly, which pushed both women off the bed onto the floor. They both shrieked a bit in unison when they fell, and then laughed together before continuing their make-out session.

“You- are the best- sister- ever.” Teresa managed between sucking on her sister’s tongue and trying to catch a breath. Vera hummed in contentedness.

Teresa was the one who first broke their contact, and shimmied down lower on Vera’s body, using her tongue to leave a wet trail down between Vera’s breasts, around her belly button, and finally up the shaft of Vera’s slowly hardening cock. She kissed it lovingly a few times, and then licked the bottom of the head where it was most sensitive. Vera came up on her elbows to watch, her eyes half-shut. When her dick was fully hard, Teresa began the process of swallowing it all, like she had done many times before. Rare was the time when Vera could resist her eruption when her sister deep-throated every single inch of her penis.

She depressed her tongue and drew in a breath, bobbing on Vera’s cock to slowly open up her throat. Inch after inch it disappeared, causing Teresa to angle her body appropriately so that the throbbing meat would go down her esophagus without bending too much. Her eyes rolled back in her head as Teresa passed the last barrier and descended the final couple inches; her nose pressing into the flesh above Vera’s cock.

She drew back with a high-pitched moan from Vera, who had narrowly avoided blasting her load into Teresa’s stomach. Teresa gasped for breath between thick cords of saliva, and descended yet again, squeezing her eyes shut as she took all seven inches down her throat. Up and down she went, sliding four or five inches into and out of her neck until Vera’s defenses were completely overwhelmed.

Her balls drew up against the base of her cock as Vera came down her sister’s throat. While Vera gasped and groaned, Teresa reveled in the feeling of hot semen shooting down her esophagus and into her stomach. Teresa waited until Vera quit bucking her hips, and then drew herself off of her lap with a suction sound. She licked her lips clean of spit and beamed into Vera’s eyes as she panted lightly.

There was no evidence of cum anywhere.

Vera wasn’t completely done, however. She got shakily to her feet, bringing her lover with her, and stroked her cock back to hardness, as it hadn’t deflated that much.

“I’m gonna fuck another baby into you.”

Teresa pressed her body against Vera’s at that comment, and they both fell onto the bed. Vera got behind her sister and pushed her head down, positioning her cock at Teresa’s entrance. She was already plenty wet, as she greatly enjoyed giving head, especially being able to please her lover as well as she could.

Vera pushed in, and bottomed out, eliciting a moan from Teresa that sharpened into a gasp as Vera pushed against the end of her vagina. Allowing a couple minutes for Teresa to adapt, Vera was soon after fucking her lover as hard as she could manage, Teresa’s voice tinging her every breath.

For a full fifteen minutes Vera fucked her sister, bringing her to orgasm five times. She finally pushed in deep and pulsed another load up into Teresa, flooding her insides with male cum.

Vera, completely exhausted, pulled out of her sister’s gaping pussy and lay down onto the bed next to Teresa, who was still frozen in the position she had been, with her back arched and ass up in the air, and her head and shoulders down on the bed. She was panting, lost in the ecstasy of multiple orgasms. After a moment, she sluggishly rolled on to her back and lay next to Vera.

When their breathing calmed down, it was all Vera could do to pull a sheet up over both of them before she passed out. Teresa fell asleep with a smile on her face, which lasted all night.

Day 50

Teresa woke the next morning feeling refreshed from the assuredly long sleep cycle. She stretched languidly, most every muscle screaming in protest from the previous night’s exertions. She rolled over and stretched her arm and leg over her sleeping sister’s body.

She gazed into Vera’s face in repose and smiled. Every single day there were moments like these that reminded Teresa of how lucky she was to have a sister like Vera.

She deserves a pleasurable wake-up call…

Teresa gently got out of bed and went to the foot of it, where Vera’s feet poked out from beneath the light sheet. Carefully lifting the edge, the older sibling eased herself beneath the cover and reached for her sister’s crotch…

…only to find a perfectly formed female vagina where her penis had once been.

Teresa gasped and flinched in surprise, shaking the bed enough to bring Vera out of her slumber. She blinked and frowned at her first sight that morning, a sheet-covered form sitting in between her open legs. She yawned and stretched her arms above her head and made fists with her toes.

“As long as you’re down there, how about a blowjob?”

In response to Vera’s request, Teresa tore the sheet off of her head and onto the floor. Vera was confronted with her now-smooth crotch, sporting a full set of vagina lips. Her jaw dropped and her eyebrows rose out of their frown.

“What the hell happened?”

As Teresa stared, Vera re-explored her folds, pairing the feel of her new self with old memories and finding a match. She was exactly as she was before her random and unexplained transformation nearly two months before.

The sisters’ eyes met, and then both returned to Vera’s genitals, which now, again, matched her former self. After a moment, Teresa tentatively reached out and caressed her sister’s leg, drawing a finger up towards her folds. She used a thumb to peel one lip away from the other, exposing the entrance at the base of the lips, and swiped her index finger through the damp that accumulated there. She brought her finger to her mouth and tasted it.

“You taste just like before.”

They both smiled, a feeling of normalcy returning to Vera that she didn’t know that she had missed. She was now completely woman again, regardless how viscerally erotic it was sporting a cock and balls.

“I’m glad you’re back to normal Veer, although I think I’m going to miss being fucked by your cock.”

Vera sat up and traced her older sister’s jawline. “We’ll have to make do. Maybe we can manufacture a dildo or something!”

Smiling, Teresa leaned in and kissed her sister, and then slowly pushed her back onto the pillow behind her, a hand snaking in between her legs. Vera caught a lip in her teeth and blew her breath out between her teeth.

Day 80

Vera writhed on the couch, struggling to get away from, and yet get closer to, Teresa’s probing tongue and slick fingers in her pussy. Orgasm #2 of the evening wasn’t far away.

Teresa lapped her tongue in the way she knew that Vera liked at this stage in the orgasmic build-up, and primed her thumb to come down on Vera’s clitoris at the exact moment. When Vera’s long, uneven breaths began to hasten and her head angled back and exposed her neck, Teresa mashed down and wiggled on the clitoris with her thumb. Vera hissed out her breath and brought her thighs together, trapping Teresa’s head as her orgasm released and washed over her.

The older sister continued her ministrations slower and more gently, bringing her lover down from her ecstatic high. Vera cracked her eyes open and blearily grinned at her wet-faced sister as she released her from her leg-prison. Teresa licked her slick lips and swallowed, then returned the grin.

“I forgot how much fun this was, just us girls again.”

Vera nodded in agreement, and urged Teresa to her feet. The swell of Teresa’s belly was now evident, gracefully joining her sternum and hips with a prominence that somehow turned Vera on twice as much whenever she looked at her sister. The fact that Teresa’s breasts had increased by one full size helped the matter along as well. Perhaps it was the fact that the child inside was made with equipment that neither woman knew the source of. Regardless, Teresa positively glowed with sexual energy, which had affected the amount of lovemaking sessions they shared in over the past month since Teresa discovered her condition. And since Vera’s cock had disappeared as mysteriously as it had arrived.

Vera placed her hand on Teresa’s belly and touched her forehead with her own. She had been thinking about the disappearance of her transient penis, and how it coincided with Teresa’s pregnancy. It didn’t lead her to any answers, but it was an inexplicable link between the two events that caused a twinge of unease in Vera’s gut.

Why did I grow a penis in the first place? What force was behind it? Will Teresa’s pregnancy be normal? I just don’t know.

Teresa put an arm around Vera’s shoulders and lifted her chin. Vera smiled tightly, her hand still on Teresa’s bulge.

“Everything will be all right.”

Vera nodded at her sister’s platitude. Neither of them knew anything of the sort.

But they were certainly going to enjoy themselves in the meantime.

Urging Teresa to take her place on the couch, Vera knelt in between her thighs, tracing patterns on each inner thigh with her fingernails, leading a circuitous route to Teresa’s nether regions. She leaned forward and planted a kiss on Teresa’s pussy, eliciting a sigh from above. From Vera’s current standpoint, she could no longer see Teresa’s face; it was just out of sight beyond the curve of her belly. As Vera continued to orally please Teresa’s fold, she snaked her hands around her hips to clasp Teresa’s swollen belly. Teresa covered Vera’s hands with her own as her breaths began to deepen.

Her tongue barely reached far enough to hit Teresa’s g-spot, but it was enough to start the chain reaction. Teresa began what sounded like an imitation of an old steam-powered train engine; her whooshing breaths getting more and more rapid.

She suddenly sat up with wide eyes, her hands clutching at her midsection. Vera looked up with concern at Teresa’s reaction, a string of woman-cum connecting Vera’s lower lip with Teresa’s vagina.

Teresa flexed, and her belly visibly shifted. Some fluid ejected from her vagina, and when Vera looked, she could see Teresa’s powerful vaginal muscles flex as though she was pushing something out, although she didn’t look to be in pain.

“Teresa?”

The older sibling shook her head, and then flexed her abdomen again, causing the surface area to slightly deflate.

This time, a long, thick, penis-shaped thing extruded from between Teresa’s pussy lips in direct sympathy with the decrease in Teresa’s belly size. Vera gasped and fell back on her ass in surprise. The extrusion was vaguely flesh-colored, and larger in size than what Vera had previously had in place of her vagina. It slipped slowly out of Teresa, and then angled its bulk upward, at the same angle a penis would sit while erect, and then stopped.

The girls sat spellbound at this newest of developments.

Teresa used her hands to feel herself tentatively, discovering what had come down out of her uterus, where she thought a fetus had resided. It was definitely in the shape of an eight-inch long penis, although with a head the same color as the shaft. At the base were Teresa’s vagina lips, completely normal and unchanged, except spread wide to allow this thing to hold place inside and outside of her. What it looked like was effectively a strapless strap-on, but instead of just fitting up inside the woman’s vaginal canal, it grew down and out of Teresa’s uterus; she could definitely feel that part of it.

Vera looked around the cock at Teresa, who came to a conclusion.

“This… thing is not me. It was growing inside my womb, and now it…”

Vera leaned forward and touched the cock, surprised to find that it was warm, of body temperature. Teresa gasped, feeling Vera’s touch as though the cock was connected to her nervous system. Vera turned the cock this way and that, examining it, and came to her own conclusion.

“This must be alien. Somehow it got inside me and somehow changed me to grow a penis and testicles so that I could impregnate you with… whatever is inside you.”

Teresa nodded through her confusion, agreeing with Vera’s appraisal. Things had gotten so weird that she would follow any logical thought, no matter where it went, as long as it explained what was happening to her. Despite the sheer insanity of current events, she couldn’t help but be a little turned on at what had transpired. Before she got carried away however, she decided on a course of action.

“Let’s have the computer scan me and see if we can figure out what it is.”

Vera nodded; concern etched on her face, and helped her sister lie back against the back of the couch. Vera then went over to the nearest computer and keystroked commands into the internal scanner. As the mechanical arm descended from the ceiling and circled around Teresa, Vera felt a sort of reverse déjà vu, since a couple months ago she was in Teresa’s place, scared for her body. Teresa watched the scanning beams penetrate her skin until it was finished, and then watched Vera for an answer.

Vera frowned at the computer results. “The computer can’t identify what that thing is growing out of your uterus, besides the fact that it’s living, and it has slightly altered your body to allow its presence. It doesn’t seem to be attached to you anywhere, it’s just occupying your belly.”

Teresa got up and came over to look at the scan, her cock waving back and forth in front of her. Vera pointed at the scan results.

“See, that’s it, swelling your uterus with its bulk. It doesn’t just reside there though, see your cervix is wrapped around where it comes out, and it is occupying every inch of your vagina.”

Vera looked down at where the cock was poking her arm. “And it’s occupying a good eight inches of the outside world too. It looks like the kink at the bottom that angles it up makes the exterior part to be used as a cock would be.”

Teresa nodded her agreement with the assessment, one hand resting on her prominent belly.

Vera tapped at the computer and a new display entered the screen. The results were normal, except for one thing.

“You’re putting off more than three times the amount of pheromones you usually do. No wonder I’m so turned on right now.”

Teresa’s brows raised and her mouth opened, glancing between her cock, the screen, and Vera’s half-lidded eyes.

“Seriously?”

Vera nodded, her hand brushing the member held tightly in place by Teresa’s reproductive system. Teresa backed away, her hands up in a questioning pose.

“I admit its intriguing, even a little hot to have an alien penis, but don’t you want to even think about it first? I could hurt you somehow.”

Vera shook her head. “You could never hurt me. I want you. I want your cock inside me as far as it will go.”

She followed Teresa until they were up against the couch again. Teresa decided to fold, and sat down, gesturing the sex-crazed Vera to do as she will. Vera tore off whatever clothing she still wore, and ran her tongue up the length of Teresa’s inhabitant. She put it in her mouth and gagged on the tip, not able to take very much in, but she used her hand to make up the difference.

Teresa gasped and panted at the contact, reveling in the new sensations that she was somehow feeling. Her inhibitions regarding this act fell away completely as Vera’s motions between her legs became more and more earnest and rapid.

Vera popped it out of her mouth and pulled herself into Teresa’s lap; her pussy was so wet that a viscous cord of female lubricant dripped out between her lips and splashed onto Teresa’s leg. Their breath lingered together as Teresa reached down and lined up the alien cock with her entrance. With a shiver, Vera worked the head inside her entrance, took a deep breath, and then slammed her hips down onto Teresa with a shout of sheer pleasure as the alien cock filled her insides and stretched her vagina to its maximum length of accommodation. She immediately began bouncing up and down on it, a frown on her face and her mouth open; maintaining eye contact with her sister.

Teresa could feel every inch of her new cock being massaged by Vera’s tight and soft inner folds, and loved the feeling, knowing that she was going to get her off at this rate.

Vera’s orgasm built surprisingly quickly, evident in the slow change of her facial expressions and the increasing impatience in her motions and the tone of her moans. When she reached her apex, she slammed down once more on Teresa and held herself there; sporadic shivers making her vibrate on Teresa’s lap, and their clitorises banging against one another, causing both of them waves of more pleasure.

It was at this point that Teresa noticed the slow expanding of her belly. As Vera panted her way through her orgasm, Teresa watched as her belly become more and more prominent; she could feel whatever was in her uterus was growing larger by the second, stretching her belly taught. She groaned and gasped, but by the time her belly had grown to what looked like a full term, the older sister was overcome by a primal need.

She grabbed Vera’s hips and held her against her crotch, their clits mashed together, and felt her cock slide out past her cervix another inch, and the end of her cock pushed up against Vera’s own cervix at the dead end of her vagina, and push through the entrance. Vera’s head snapped up at this push, her breaths shallow, her eyes wide.

“What—“

Her gaze then alighted on Teresa’s now-huge belly.

“Your belly, it-“

It was then that the creature inside Teresa contracted, and hard, too. Somehow, the end of the cock inside Vera latched on to her cervix, creating a seal, and then began jetting some sort of fluid into Vera’s uterus. Vera felt it all through an erotic haze, and placed her hands over her lower belly, feeling the exchange of fluids between the two women.

Teresa clenched her belly muscles, facilitating the deposit, feeling the rushing of liquid from her belly down through the member that occupied her vagina, and out into her lover, where it climbed the buried shaft and exited into Vera’s uterus, swelling the organ.

Teresa’s belly began to deflate slowly, and at a concordant rate, Vera’s belly began to expand as she was pumped full of fluid. Both women could only watch and feel as the exchange happened, neither willing to do much to stop it through a haze of pleasure. Vera had to brace herself against the back of the couch as her belly grew outward.

Teresa stopped her flexing when the creature inside her did; her belly had decreased in size until it was almost normal, but for the creature itself still residing within her. Vera was full to the brim it seemed with alien liquid, her eyes half-lidded and her hands wrapped around herself.

At that point, the creature in Teresa’s belly shifted and began to spread her cervix. Teresa gasped and panted in surprise, but no pain, and the creature exited its home and pushed her vaginal walls to their outermost extremes to allow passage. With rapid breaths, Teresa helped push the creature out of her, until it emerged as a grey ball tapering down to where the cock portion of it was stuck up inside Vera. With a slick popping noise, it came out of Teresa, who immediately put her hand over the opening of her vagina, feeling it pulse and shrink back to its regular size.

She watched as the creature pushed all of its cock up inside Vera, whose expression and breathing was similar to Teresa’s a moment ago. The creature’s taper pushed Vera open wide enough to allow egress as it drew its bulk up closer to her nethers. Teresa watched in wonder as she saw her sister’s vaginal lips expand over and around the thing as it moved into her canal with sporadic movements. With every flex of the creature, it opened her lips wider and wider until it was engulfed, and moved up her vagina. It disappeared from Teresa’s view, her exterior folds shrinking down around it until they were a normal set of folds surrounding a vaginal entrance topped by a clitoris, but should see the bulge of Vera’s pelvic bone as the creature moved up inside her beneath it.

With a gurgle, the creature snapped itself into Vera’s fluid-filled uterus, causing the minor bulge beneath her skin to merge suddenly with the larger bulge that was her belly, and a gush of clear liquid shot from her vagina.

With the effort over, both girls collapsed on the couch, nether one of them completely sure what to do next. They both still felt amazing; Teresa more empty than before, and Vera more full than she had ever felt. Teresa looked over and laid her hand on Vera’s hard belly, and Vera reached up and clasped her sister’s hand.

“We did it…” Vera said in a breathy voice.

What they had done, Teresa wasn’t sure, but she felt the same sense of satisfaction as Vera did.

Day 265 (Epilogue)

At the precise moment that their ship emerged from the null-space that they had travelled through for the past nine months, Vera felt a heavy contraction in her bulbous belly.

She groaned, her eyes going wide, and unstrapped herself from the pilot’s chair, struggling through the weightlessness to the hatchway. She oriented herself and actuated the hatch, emerging into the common room clutching her stomach.

“Rees! Its time!!”

She heard a clunk from the maintenance area, and Teresa soon appeared, tossing a mechanic’s apron aside.

“It’s time??”

Vera nodded, slowly lying back on the couch and spreading her legs. The creature inside her was doing somersaults it seemed like. But she was absolutely sure that it was about to emerge for the first time since it had come out of Teresa and took up residence within Vera.

Teresa got down in front of Vera’s spread vagina entrance, watching her belly roil and shift. Her sister’s opening was clenching and unclenching as if anxious.

With a guttural yell, Vera’s stomach depressed, and all at once the grey creature, now twice the size it had been when it entered Vera some five months prior, gushed out of Vera’s vagina with a flood of clear liquid. It fell past an astonished Teresa and onto the floor where it flopped for a moment. Teresa backed up, staring at the new arrival. It raised itself up on one tentacle, and reached out with another to touch Vera as she panted her way back to normalcy, and then reached out to touch Teresa.

Both women gasped as a thought – more like a memory that has always been true – entered their minds.

The creature was part of the null-space they had travelled through. It had entered their vessel because it wanted to leave the vast wastes that constituted a lack of a plane, and the only way it could do that was being reborn through a tangible being like themselves. Now that it was free of the space between planes, it could leave their bodies and explore the universe. The last part of the explanation was explicit gratitude for their assistance in opening an entire new universe to it.

Both women grinned, Teresa running a hand down the tapered grey body of the creature, causing it to shudder and twist a little. It then used its tentacles to “run” at the nearest wall, and completely disappear through it.

The women went over to the nearest viewport and gazed at the retreating silhouette of the creature against the sun that they had been sent to explore. They held hands and grinned at the wonder – and the pleasure – of the universe.