Author's Notes: This story is inspired by the long-gone Literotica story "Aliens Use Sex to Invade". It is primarily Science Fiction and Fantasy but has elements of Gay Male, Group Sex, Lesbian, voyeurism, and Incest/Taboo. All Characters are over 18 years old and are not intended to be based on real individuals.
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Peter Jefferson, Age 23, Exo-Archeology Division.
The morning after everyone got quarantined thanks to Peter, they were given a clean bill of health, more so now that everyone had spontaneously grown in size...everywhere. The medical staff of 'Aldrin One' were amazed at the change in the team's bodies that happened overnight, but could find no explanation as to how this happened.
On the surface, each one of the men had grown in height and muscle mass and had their erections extended by a few inches in length and girth. The women, meanwhile, hadn't had an obvious change as of yet, but inside, their hormones and libidos had been altered to become hornier and more accepting of sexual activity.
The lead scientist, a woman named Samantha Anderson, wanted to keep the team in quarantine a bit longer, but protocols were to release them at the end of confinement, so she asked each of them to return for a follow-up within the next couple of days.
Upon their release, Laura and Emily were given their clothes to put on, which they seemed hesitant to do so, given how vigorously they fucked the previous night, not bothering to sleep and reeking of sex. They claimed they didn't want to stink up their clothes, but in reality, they wanted to keep fucking and felt that they were too hot and bothered to be comfortable in their uniforms. As it turned out, they were right. As soon as they got dressed, their uniforms felt tight around their bodies and they wanted nothing more than to take them off.
They ignored the impulse, barely, as they left and returned to their barracks alongside Laura's husband John, who needed a new uniform given that he'd grown in size and no longer fit into his medium fatigues. His body, which was a medium build with a size 30 waist, had doubled and now required an extra large size shirt and size 35 waist.
Meanwhile, Peter and Jack, who weren't military, but rather part of the science division, were given their normal clothes, which they reluctantly received. Secretly, they discarded their underwear, deciding to go Commando. As the two of them left and returned to their floor, they had dropped all pretense and were now admiring each other's newly discovered physiques in their tight-fitting clothes.
Everyone who was affected by the alien parasites was now acting as an incubator. Jack suspected that the reason behind their newfound aggressive increase in their body mass was due to an infection they picked up on the ship, and not the parasite, itself, since he visibly saw it destroyed by the marines. He chalked it off to hormonal angst and blowing off steam, and that's why he and Peter got so horny and seduced a guy seven years older than them into sucking their cocks and letting them fuck his virgin ass.
Regardless, whatever animosity he felt for Peter evaporated when he started admiring his fellows' new bodies and pornstar cock. Peter, likewise, was thrilled that Jack was no longer glaring at him, but rather staring at him with immense thirst and desire. He decided to test a theory he had and stripped his shirt off.
"It's too hot in here to wear a shirt." He lied, fanning his face with the crumpled-up garment, "What do you say, Jackie? You wanna be topless with me?"
Jack didn't hesitate and stripped off his shirt as they departed the elevator to their domicile floor. Even though their rivalry hadn't completely evaporated along with their inhibitions, Jack had to one-up him and dropped his pants as well, letting his perpetual hard-on free.
"I'd rather be completely naked than just be shirtless, Pete!" He said, using the long-gone nickname that he'd once used when the two boys first met back in high school. Back when they still liked each other.
Peter smirked at the mention of the long-dead nickname and the fact that Jack was erect, and so brazenly nude in the middle of a public hallway. Surely there were active cameras monitoring the area...come to think of it, being watched by security sounded sexy. Peter's mouth twitched into a sly grin as he followed suit and dropped his own pants, not bothering to pick up his clothes as he left them sitting in the elevator as he and Jack stepped out.
The two men started to admire each other's naked forms as they walked to Jack's domicile. Jack, who had grown from a lean swimmer's build to a whopping military thick build, had a now nine-inch dick, which stood erect and unchanging, his balls dangling and filled to the brim with cum, just waiting to be released.
Without hesitation, Peter extended his hand and grasped the nine-inch cock, stroking it gently as they reached Jack's door. Jack, smiling at the pleasure in his groin, lifted his left arm, where on his wrist he wore a watch and multi-tool. The multi-tool was an electronic device that held all sorts of functions, mainly a key to his domicile, as well as a music playlist, internet connection, and personal communicator, which connected to an implant in his ear.
The door's lock clicked as Jack waved his hand over the sensor, and the doors slid open, allowing both men to slide through undisturbed. The second the doors slid shut, both men smashed against each other, kissing and groping the other's body, roaming over the pecs and glutes, pinching in random places to increase the level of arousal that was already plenty high, thanks to their parasites inside.
When Jack and Peter, alongside John, Laura, and Emily, got infected, the parasites within them started to alter their bodies to be more accepting of sex, as well as more desirable to attract mates. The five of them were now walking sex gods.
The nations of the world had long ago abandoned monotheism in favor of a resurgence in polytheism, embracing all Gods of the various pantheons throughout the world. Many Western cultures embraced the Greek and Celtic gods, praising warriors like Ares and Mananan Mac Lir, and paying tribute to Sex gods and Crafters like Aphrodite and Aengis, along with Dionysus, Haephestus, Goibniu, and several others. Meanwhile, the Eastern religions embraced the Hindu gods, and some of the German and Russian origins embraced the Viking Gods like Thor, Odin, and Loki.
Right now, Jack and Peter were praising Eros, the god of sex, by pleasuring each other as a prelude to a wild night of non-stop fucking.
Meanwhile, down in the military barracks, Laura and Emily were getting frisky with John. All throughout their night in quarantine, the two women devised a plan to seduce John into a threesome. Laura took the lead, like she did in most cases, being ranked higher than John. She was a major, while John was a Lieutenant. Emily, meanwhile, was an exo-biologist, but she lived with the two of them in military housing, mainly because she and John lived most places together.
John and Emily were twins, born and raised together. When they were teenagers, John started getting random erections whenever he was around Emily, and quickly realized he was attracted to his sister. Emily, meanwhile, started developing feelings for John, but she knew she could never express them, since incest was still outlawed throughout the world, though some laws allowed for families to explore 'Familial Love' practices in order for parents to teach their kids about sex and to prepare them for adulthood.
These practices included introducing them to the opposite sex through non-sexual nudism, as well as a fundamental sexual education program designed to instruct those in romantic love vs sexual desire and gave a full list of sexual identity. Western society had evolved to allow for this program to be taught in schools while more traditional families were allowed to teach their kids on their own terms.
Any complaints were handed over to a board of education and evaluated. Most people who complained were given a slap on the wrist for bothering the board's time, and a majority of people grew to accept the curriculum.
Back in the present, John was feeling very uncomfortable in his uniform, feeling warm and constrained. The shirt was too hot, and his pants were too tight. He also kept stealing glances at both his wife and sister, admiring how their skin glistened in the light of the barracks. When they reached their personal apartment, Laura took the lead and stripped off her clothes, complaining that it was too hot in them and that she was glad to be rid of them.
John let out a wolf whistle as his wife strutted around the apartment completely naked. Emily, meanwhile, felt emboldened and followed suit, making an effort to show off her body as she stripped naked as well. Soon, the two women were stretching in front of John, who no longer bothered to hide his pleasure and sexual desire for the two women, regardless of the fact that one of them was his flesh and blood sister.
Laura glanced at John's very present bulge and smiled, "Johnny, sweetie, why don't you join us?" she asked, sexily, "I'd love to see your new body. You're so much taller than you were yesterday. I bet your cock is hard, just staring at us."
John smiled broadly and literally ripped off his clothes, tearing the fabric as he did so. Clearly, his strength had been enhanced along with his libido. As his shirt was ripped in half, Laura and Emily clung to each other in sexual amazement, their hands clamped down on each other's pussies, a finger inside each. They gently rubbed each other as they watched John pull the belt from his pants with such force that it slapped into his chest, but he ignored it as he dropped his pants, revealing a fucking eleven inches.
Emily gasped when she saw the large cock, her eyes widened in lust. She quickly let go of Laura and abandoned the plan altogether, crossing the distance between herself and her brother and dropping to her knees, took his cock in her hand and swallowed the first half into her mouth, and started to suck it with immense vigor.
Laura, meanwhile, crossed the distance and started kissing her husband, who had a look of shock in his eyes at the sight of his sister sucking his cock. She locked lips with him and drove her tongue down his throat, moaning as he returned the favor.
"She's had a crush on you for years!" Laura said, after releasing her tongue-lashing kiss, "She's wanted to fuck you for just as long! We talked last night while we fucked! We had the plan to seduce you, but clearly, she couldn't wait any longer, not after seeing this fucking beautiful cock!"
"I can tell. Gods above, she's good at that!" Said John, his voice cracking with ecstasy, "I've wanted to fuck her for years as well. I kept thinking of her before I lost my virginity. I wanted her to be the first pussy I had but I knew it was wrong. I had to settle for Becky Barnes in my 12th-grade English class. Bombshell beauty but a total airhead. She came five seconds after I entered her and I came in her five minutes after that."
