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Biological Imperative	By : GeorgeGlass Category: +G through L > Lilo and Stitch Views: 43392 -:- Recommendations : 4 -:- Currently Reading : 2
Disclaimer: I do not own Lilo & Stitch or its characters. I made no money from writing this story.

Chapter List
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Chapter 3
Lilo felt strange as she walked home from school. Her chest had been tender and achy sometimes during the last few days, but it was especially bad today. And that morning, when she took off her nightgown and looked at her naked body in the mirror, she could see why. Although Lilo’s plump body had always had what she mentally called “booblets,” they had gotten slightly but visibly larger in the past few days.
They’re just swollen, I guess, she thought. If I wait, maybe it’ll go away.
It wasn’t true, though. Lilo didn’t know it, but inside, her body was changing. In her chest, where Stitch had rubbed so much of his semen into her skin, her mammary glands were awakening and growing. Her ovaries, which normally would have remained dormant for another four or five years until Lilo reached her natural adolescence, also had become active, getting ready to begin releasing eggs on a regular basis. And the walls of her uterus were preparing themselves to be implanted with those eggs once they had joined with a potent sperm cell.
She was becoming fertile.
***
That day, Lilo’s hula practice was cancelled, so the girl arrived home early. She was about to unlock the front door when she heard talking inside.
“Stitch need Nani again,” she heard her alien friend say. “Nani take off clothes.”
“Stitch,” Nani said, her voice tremulous. “Please, we…we can’t keep doing that.”
Keep doing what? Lilo thought.
She crept around to a window, where she could see Nani and Stitch in the living room by the sofa. Stitch’s two black members were big and hard again.
“Stitch must do,” the alien said, “or Stitch could die. Nani take off clothes, lie down on couch. Will not take long—Stitch promise.”
Nani just looked at him with big eyes. Then Stitch added, “If Stitch do to Nani, won’t have to do to Lilo.”
Lilo recognized the way Nani exhaled and tilted her head down. It was what Nani did whenever Lilo had just talked her into something.
“All right,” Nani answered quietly.
Slowly, she undressed. Stitch watched with interest as Nani first removed her blue tank top, then her light-blue bra. Now that Nani was topless, Lilo noticed that her sister’s boobs seemed a little bigger than they used to be.
Is she having the same swelling problem as me? Lilo wondered.
Stitch reached up and felt Nani’s breasts, smiling toothily at her.
“Mmm, Nani growing,” he said. “Good, good. Stitch will make Nani very pretty. Take off pants and lie down, now.”
Hesitantly, Nani slid her tan shorts and black undies down to her feet and stepped out of them. Then she lay down on the couch. It was covered by an old afghan, which Nani had thrown over it a couple of days earlier.
Lilo was puzzled. Stitch didn’t need Nani to take all her clothes off to put one of his things in her mouth and shoot his stuff on her chest with the other thing, like he had with Lilo. So what was he going to do?
“Yes, yes, good,” Stitch said. “Open legs wide now.”
Nani did as she was told, spreading her tan thighs as wide as the amount of space on the sofa would allow. Lilo could see the pink of Nani’s punani (Lilo had overheard that word in a whispered conversation among her hula classmates, and she’d thought it was hilarious how much it sounded like her sister’s name) beneath a tuft of black hair.
Stitch jumped up on the couch, landing between Nani’s open legs. The heads of both of his cocks were glistening with the precum that oozed plentifully from their holes.
So it didn’t matter that Nani wasn’t wet. Stitch had no trouble pushing the head of his lower cock into her open pussy, sinking inch after girthy inch of his member into the nineteen-year-old’s reluctant body. The girl groaned.
“Yes, yes, Nani take, good girl,” Stitch babbled, clearly enjoying the sensation of pushing his length into Nani’s cunt. “Nani-pussy just right for Stitch-cock.”
Pussy, Lilo thought. That’s a funny word for it. Not as funny as punani, though.
Stitch pushed until his lower cock was all the way inside Nani, making her wince slightly as it hit bottom within her. Stitch’s upper cock lay hard against the girl’s flat stomach. Then he began to push his cock slowly in and out of her.
Lilo was puzzled by this. What was Stitch doing? It looked kind of like the thing he’d done with Lilo’s mouth, but obviously it wasn’t that. The seven-year-old only knew a few things about the birds and the bees, and although what she was seeing now seemed to be related to that, she didn’t know exactly how any of that stuff worked, so she couldn’t quite make sense of it.
Nani was completely unaware that Lilo was watching. In fact, she was unaware of just about everything except for the thick alien cock being pushed into her over and over. Stitch’s member was more than half again as big as David’s, both in length and in girth, and it felt like it was stretching Nani’s channel to its limit.
As Stitch pumped her slowly, Nani briefly flashed on the moment when, four days earlier, he’d pushed his full cocklength into Nani’s cunt for the first time. Through the haze of fear, discomfort, and violation, the teenager had been surprised that she had that much room inside her.
That first time, Stitch had come into Nani’s room late at night, his two penises half-turgid and growing firmer by the moment, and told her to take off her nightgown. She had tried to reason with him, or at least talk him down, but to no avail. She’d been thinking about making a run for it when he told her—then, as now—that he needed her to do this so that Lilo wouldn’t have to. That thinly veiled threat was what got her to cooperate. Nani was nineteen and had a little sexual experience, albeit only with David. Lilo, on the other hand, was only seven—an innocent child. Nani couldn’t let this happen to her.
Which, Nani thought, was the sole reason why she was now lying on the sofa, legs spread wide, as this alien creature used her body to sate his needs. Yes, fear for Lilo was the only reason why she accepted this unwanted intimacy. It had nothing to do with how the thickness of Stitch’s cock stretched her opening so wide that the tissue encircling it pulled rhythmically against her clit with each of the blue alien’s slow, deep thrusts. It had nothing to do with the way his second cock (a second one!) lay heavily on her belly, rubbing up and down as Stitch fucked her, a constant visual reminder of just how big and thick that cock inside her was.
Stitch, driven by his urges, began fucking Nani a little faster. The sight of her growing breasts jiggling with his thrusts was adding to the already considerable—and extremely pleasurable—stimulation he was receiving from the movement of his lower member within her tight female channel.
The diminutive alien didn’t know why his irresistible, irrepressible urges had driven him to do different things with Lilo and Nani. He hadn’t felt a burning need to force his cock down Nani’s throat the way he had with Lilo; instead, he’d needed to do this other thing with her, to put his cock in her female hole and move it inside her. And he’d needed it quite a bit, as this was the third time in four days.
It felt good to do it, too. In fact, everything he’d done with the girls during the past week had felt good. When his cocks were inside Lilo and Nani’s warm, tight channels, moving against their inner walls, the sensation was closer to pure bliss than anything Stitch had experienced before.
Lilo’s eyes were glued to the action now as she tried to figure out exactly what was happening. It wasn’t clear to her whether Stitch was hurting Nani, or whether she liked what he was doing. It kind of looked like both. In contrast, Stitch was obviously enjoying every second of this, given the unmistakable look of pure pleasure on his face as he pumped his thing in and out of Nani.
“Hmm, yes,” Stitch said happily. “Nani-pussy so nice, so tight…”
Nani wished that he wouldn’t say these things. Allowing Stitch to fuck her was degrading enough. She consoled herself with the thought that maybe he didn’t mean them to be degrading; maybe he was just saying what was going through his head. Although she wondered where he had learned those words.
Stitch increased the pace of his fucking, and these thoughts went out of Nani’s mind. In spite of herself, she could feel—between her legs and in her belly—an orgasm beginning to rise. Seemingly of their own free will, her hands went to her newly enlarged breasts and began to tug and pinch her stiff, deep-brown nipples.
“Ahhhh,” Stitch said, enjoying the sight. “Nani-titties feel good, yes? Stitch will make even bigger.”
“N- No…Stitch…” Nani gasped, the rhythmic pressure on her clit interfering with her ability to form words. “I…I don’t…want them…bigger…”
“Nani will like,” Stitch hissed, pumping her faster still. “Nani will see.”
Both Stitch and Nani started making sounds with each of Stitch’s increasingly rapid thrusts. Lilo remembered how it felt when Stitch pumped her throat like that, and she was glad that at least Nani didn’t have to be afraid of choking to death, or of drowning when Stitch finished.
“Nnnh! Nnnh! Nnnh! Nnnh!” Stitch grunted, pumping Nani’s pussy fast and deep. His eyes were squeezed shut, and he felt that moment of unparalleled bliss coming closer and closer.
Nani was shouting “Ah! Ah! Ah! Ah!” as her body moved back and forth on the sofa with the force of Stitch’s thrusts. Her fingers were pinching and squeezing her nipples hard now, hard enough that it would have hurt under other circumstances. And the repeated impact of Stitch’s cockhead against the mouth of her womb did hurt, but it also felt so, so good that she could barely stand it.
“Nnngh! Nnnnngggh! NNNNGGGHH!” Stitch grunted, and then Lilo watched as Stitch shot long, thick ropes of cum from his upper cock that splattered thickly across Nani’s face, chest, and belly.
“AaaaaAAAAAAAAAAH!” Nani cried out. She thrashed beneath Stitch, but his four small, powerful hands gripped her thighs, keeping her impaled on his lower cock as his upper one continued to coat the entire upper half of her body in his translucent seed.
It was almost half a minute before Stitch finally finished geysering cum across Nani’s body. Lilo could see Nani’s stomach bulging a little—at least until Stitch pulled his lower cock out and what looked like a gallon of cum flooded out of Nani’s gaping pussy. Nani lay there limply, legs wide apart, as Stitch’s prodigious load poured out of her.
Stitch paid no heed to the mess. He quickly climbed onto Nani’s stomach and used all four of his hands to massage his cum into her breasts.
Nani would have been helpless to stop Stitch even at her best, which she certainly was not. Being fucked to a wracking orgasm by the alien’s inhuman cock and then having her womb stretched like a balloon by his tremendous load had left her feeling as weak as a newborn kitten. The only resistance she could put up was verbal, and even that was pitiful.
“No…Don’t…” Nani said weakly as Stitch kneaded her breasts in his hands, working his semen into her skin.
“Stitch must do,” the alien replied, and Lilo could hear a note of genuine apology in his voice. But she also heard eagerness when he added, “Must make Nani bigger. Will be very pretty.”
So Nani simply lay there while Stitch kneaded and massaged her breasts over and over. When he finally finished, he got up off of her and then scampered upstairs.
At that point, Nani dragged herself to her feet, then pulled the cum-soaked afghan off the couch and took it to the washer. Then she went upstairs, too.
Only then did Lilo go inside, resolving to say nothing about what she’d seen.
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Biological Imperative