“Puter, why am I panting in the simulation?” Tica asked, looking with interest at the shuttle wall where human mating was simulated by the shuttle computer.

“The female is approaching orgasm, the reaction is natural,” Puter’s voice sounded through the speakers.

Carla woke with a start and stared at the screen where her young daughter, still just a child, was depicted having sex with her father. “Puter, stop!” Carla shouted and the image froze with the man’s cock deeply embedded in the child’s hairless cunt. “Close the simulation, I mean!”

“Mommy?” Tica asked nervously.

“Puter, block all sexual content!” Carla said before turning to her daughter.

“I was just studying,” Tica said, close to tears.

Carla opened her mouth but closed it again, completely lost for words. Their situation aboard the emergency shuttle was somewhat unique: Tica had been born a few months after the evacuation, and had never met any human except her mother, Carla. To make the situation even worse, the shuttle had not been equipped with the resources to keep two humans alive, and everything non essential had been converted into food, including clothes.

Unbidden Carla’s eyes traveled down her daughter’s body, noticing her flushed and aroused sex. “This may seem odd, but an adult may not have sex with a child, and a father and daughter, regardless of age, should not have sex either.”

Tica nodded, accepting the facts.

“Just watching a simulation of it…well, it isn’t something you do with your mother around,” Carla went on. “You will just have to wait with that kind of stuff until we reach earth.”

Tica sighed. Earth was still years away. “What if I wait for your next sleep shift? You wouldn’t be aware of me studying anything. And I could use you and daddy for the simulation instead.”

“No simulations,” Carla said, a vivid image of her daughter’s bulging labia around a man’s cock flying through her mind. “Look at yourself if you are curious.”

As soon as Tica entered her sleep shift and fell asleep, Carla started reviewing the logs of what exactly her daughter had watched. “Puter, shield Tica from all sound and unblock sexual content,” she ordered. “Restore previous simulation.”

The simulation appeared in live size on the wall, and continued playing from where it had been stopped. The images and sounds took Carla by complete surprise, she had only wanted the logs in a plain text format.

Tica in the simulation wasn’t just being penetrated by her father but actively met his thrusts, moaning like a little porn star. Tica’s breath caught and she lifted her butt up in a silent, desperate plea for sexual release.

“Puter, stop the simulation,” Carla said, her mouth dry. “Is this simulation realistic?”

“Ignoring the genetic relation and age gap, the simulation is realistic.”

“But she’s about to…orgasm,” Carla said in a whisper.

“Orgasm is a natural response to sexual stimulation,” the computer said.

Carla had many times watched a similar simulation but with her in the female role, and couldn’t help getting wet. She told herself that she was only interested in her ex-lover, and that her daughter had nothing to do with it. Floating in the zero-g, she spread her legs and placed a hand on her heated sex. With circular motions she started pleasing herself. “Puter, continue simulation,” she whispered.

The man’s cock hit home hard, his balls slapping against Tica’s butt. Tica let out a gasp, and her eyes rolled back. A moan followed and her hips started buckling on their own, sending shivers down her legs.

“Puter, zoom in on their sexes,” Carla said, her voice taught as she worked her pussy.

The close up showed every detail of Tica’s cunt, and his cock. Her muscles squeezed him rhythmically, which brought him over the edge as well. With a thrust and a cat like howl from Tica, his cock started pumping seed into her.

“Puter, make him ejaculate indefinitely,“ Carla croaked and watched her daughter’s pussy overflow. Globs of cum leaked out, running down her ass.

Imagining herself being part of the simulation, as either her daughter, or the man fucking her, Carla came, spraying the screen with a squirt. “Oh god!” she cried out, shivering and jerking as if in a seizure.

When Carla opened her eyes after her orgasm, she saw the man pull his dick out, still squirting his seed everywhere. Tica’s pussy remained wide open, worn to the point when her muscles just wouldn’t work. Her insides as well as outsides, were smeared with her father’s seed, and in her depths, the entrance to her completely coated with semen.

Feeling worn and guilty, Carla erased all records of the simulation and spent the following hours frantically cleaning both herself and the shuttle to remove all traces of her masturbation. She didn’t even want to think about the possibility that she was sexually attracted to her daughter. With a mental effort, she pushed it all out of her mind.

Tica found her mother unusually cheerful the next day, and was happy all the fuss about her studying mating had blown over. Still, it was a shame that she couldn’t use Puter anymore for sex-ed. Lately, it had become her favorite subject but wasn’t very fun if all she had to work with was herself. She couldn’t even see what she looked like that well.

Towards the end of her mother’s sleep shift, Tica crawled into the alcove with a bright idea. If she couldn’t use Puter, and wasn’t able to see her own sex, studying her mother was the obvious answer.

Carla was such a heavy sleeper, and didn’t even stir despite her sleep shift going over time. Taking matters into her own hands, Tica spread her mother’s legs. Carla was a very slim woman, and Tica couldn’t help wondering if her mother got enough food. Carla’s ribs showed and her vulva stood out high against her abdomen. But on the other hand, Carla had big round breasts and a butt which swung back and forth when she walked.

With two fingers, Tica spread her mother’s pussy open. It was hairless and soft just like hers, but looked differently and was glistening with moisture. Studiously, she silently went through the outer and inner lips, the vaginal entrance, pee hole, and clitoris. The clit was a bit difficult because it hid under its hood but came out after some fiddling, and then stayed out like a little pink pearl.

There was still one vital part left of her mother’s sex: the vagina itself. Carefully, she pulled the entrance open and laid down on her stomach to peek inside. Pink, rippled flesh, coated with moisture was inside. By accident, Tica’s pinkie pressed against her mother’s clit, and as if it was a button, the fleshy ripples opened, showing the depth of the vagina, all the way back to the pink cervix.

Tica touched her mother’s clit some more, wondering why the cervix remained closed. There was no way a baby could fit though there. On the other hand, not all doors were automatic. Some needed to be opened by pushing.

Making her mother’s cunt open wide, like a fish gasping for breath, Tica slid her hand inside her mother, and pushed against the cervix.

“Tica!” Carla shrieked and clamped her vagina down painfully hard on her daughter’s hand.

“Let go, mommy!” Tica cried and desperately started pushing the clit to make the vagina open again.

Carla’s hips buckled and she let out a moan, much like Tica had in the simulation while mating. Her mother’s vagina relaxed, but Tica wasn’t sure if she was allowed to pull her hand out. Her mother’s vagina had held her firmly in place after all.

Carla took a deep breath. “Tica, I told you grown ups and children aren’t supposed to have sex.”

“But we are girls, mommy. We can’t mate and have babies.”

“Well, see,” Carla said, sounding strange, “mating feels very good, so most of the time it isn’t for having babies.”

“So this feels very good to you?” Tica asked, turning her hand around inside her mother to show what she meant.

Carla gasped and nodded, words failing her.

Wanting her mother to feel good, Tica turned her hand again.

“No please, Tica,” Carla begged. “Don’t, or mommy will orgasm.”

“Orgasm is bad?”

“No, not directly…just slowly pull your hand out.”

Slowly, almost not moving at all, Tica started pulling her hand out. Calra panted heavily, her clitoris swollen, and her juices flowing. Her abs clenched and the clit hid under its hood again.

“Oh no,” Carla gasped as her cunt clamped down on her daughter’s hand. “I’m so sorry,” she cried as her body turned against her will and had its first orgasm induced by another person for over a decade. “Mommy’s orgasming,” Carla squeaked, before her mind was overrun with pleasure. Since it had already come this far, her addled mind though, she might as well take it all the way. “Please, Tica,” she moaned and placed her daughter’s free hand over her clit. “Rub me, just this once.”

Tica watched her mother in fascination. She understood that Carla was in some kind of pleasurably bliss, but had never imagined there could be something good enough to make your entire body shake.

After a moment, Carla pulled Ticha’s hand out of her vagina and made her stop rubbing.

“You are done doing that orgasm thing?” Tica asked. “You can do it a bit more if you want to. I don’t mind.”

“I’m fine,” Carla said, not meeting Tica’s eyes.

Tica then laid down, spreading her legs for her mother. “Put your hand in,” she said. “I wanna do an orgasm too.”

“I can’t do that,” Carla said. “I tried to explain but it is terribly wrong for a mother and daughter to do these kind of things. It only happened to me because I couldn’t stop it.”

Tica remained on her back, not saying anything, but it was clear to Carla that all she heard was a harsh rejection.

“You can do it all you want to with other people once we get to earth,” Carla said, placing a comforting hand on her daughter’s thigh and then quickly removed it when the sexual implications struck her. Carla’s eyes were drawn to her child’s sex, which was just as flushed and aroused as she knew it would be. “I’m very sorry that I’ve made you feel this way.”

“It’s over five years left, mommy,” Tica said, tears in her eyes.

Five years of not daring to touch her daughter, and warding off her advances, would not be possible. It would ruin them, and they were both so horny. Leaning down, Carla placed a hesitant kiss on Tica’s mound. The girl gasped and Carla deepened the kiss, tasting her child’s pussy.

“Thank you,” Tica purred, running her fingers through her mother’s hair. “Can you put your hand in now?”

“That would hurt you, sweetie,” Carla said in between little kisses.

“Mommy,” Tica begged and Carla carefully pushed a finger inside her wet daughter.

“Did that hurt? Anymore and I’m sure it’ll break you open.”

“Alright then, do that,” Tica said, determined to shiver in pleasure just as her mother had.

The second finger hurt, just as Carla had predicted. “Your opening is too tight.”

“Mommy!” Tica cried, the pain turning her determination into anger.

Carla knew she shouldn’t, but watching her fingers slide in and out of her daughter, grinding against the hymen was too enticing. A third finger produced a rush of blood and a gasp of pain. Her daughter’s cunt was obscenely stretched, turning her pink flesh dark red. Tica’s labia was pulled open wide enough to expose her tiny clit. The forth finger stretched her cunt to the point where it looked as if she was giving birth.

“Mommy! Stop, I can’t do it!”

“Hush sweetheart, I’m almost inside,” Carla said and forced her hand inside her daughter, who convulsed and clamped down hard. She lost control and started to pee, which Carla quickly drank before it could burn her broken hymen.

“When does it start to feel good?” Tica said, still in very much pain.

“Just look at me licking your pussy,” Carla said and ran her tongue over her daughter’s clit.

“Do that again,” Tica said and moaned softly when Carla did.

“I’m going to start fist fucking you now,” Carla said and started sliding her hand out. Tica’s cunt was just a little more wet than tight, making the movement a pleasure. As Carla pushed her fist back inside, she noted how it made her daughter’s abdomen bulge. She really had stretched her daughter to the limit, and despite all the pain, Tica was approaching her orgasm quickly.

“More, mommy, do it more,” Tica panted.

“I’m going to make you orgasm so hard,” Carla whispered, fisting her daughter faster.

“Mommy,” Tica gasped. “It’s going to happen. I’m going to orgasm.”

Just as she had in the simulation, Tica raised her butt off the bed, holding her breath as her body started fucking instinctively. Despite her not yet being fertile, her body did its best to impregnate itself. Her cunt started spasming, and her body started to shake. “Mommy,” her lips formed the word but she was still holding her breath and didn’t make a sound as her orgasm hit her. Then she gasped for breath and started grunting as the most intense pleasure washed over her in waves.

Carla watched with motherly pride, silently counting the spasms, and carefully tasting her daughter’s secretions, so that she would always remember her daughter’s first orgasm.

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