Note for readers: This is an adult homosexual male erotic fiction story which describes fictional sexual activity between consenting adults. Readers under the age of legal adulthood in their place of residence or who are not interested in homosexual erotic fiction or who reside in locations where posession of this material is not legal should please stop reading here.
Thank you for your kind emails and instant messages. "Phase 4" is the final phase of significant transformation I have planned for this story line, but I plan to write at least one more part to this story after this chapter, perhaps two, dealing with consequences and aftermath. I hope you will enjoy them.
Enlargement: Phase 4
The next evening the timers built into all the GID nanobots hit phase 4, and the next round of changes began.
Men everywhere started having tingling feelings in their cocks and asses again, but few noticed becuase most either were already having sex or just took it to mean they felt like having sex... which they felt like most of the time these days, so it wasn't worth much concern. But, after about 12 hours, some men started noticing that their cocks had grown again. Indeed, all cocks were growing again, but more slowly this time, and in some cases slowly enough that the men might not notice for a whole day. However, with all the focus on sex since GID, everyone eventually did notice.
Before Phase 4, cocks had grown into the 9 to 12 inch range. By the end of the first day of Phase 4, most had grown into the 12 to 14 inch range with substantial added thickness, and growth was starting to accelerate. Along with this growth came a kind of tingly, empty feeling in the ass, and the first 8 to 10 hours of the second day of Phase 4 were accompanied by frantic fucking among a world population of men who all suddenly wanted a cock in their ass.
By the middle of the second day of Phase 4, it was pretty obvious to everyone that cocks were going to be enormous. Huge. Monsterous. Indeed they already were, and pants were starting to become significantly problematic. Men were starting to have to walk around with their massive cocks out in public as they tried to figure out what to do about clothes... but of course, the sight of so many hot men walking around with their cock out started to lead to impromptu sex in the streets. Nobody intervened... there weren't enough female cops to really do anything about it, and the men were too busy being distracted by new growth.
Cocks were getting absurd, and even the sex-crazed men of Earth knew it. Many felt shocked, many were upset, but everyone knew that nobody knew how to stop it. Most men got together in small groups to get naked together, sit down, stare at their cocks and stroke together. They didn't know what else to do.
By the end of the second day of Phase 4, About 40% of men had reached their full new cock size, and the rest would within a day unless they took longer because they weren't eating enough to power and supply their nanobots. The results were definitely shocking. The average cock now fell into the range of 18 to 22 inches long, about 6 inches thick, and about 14 inches around. When hard, most guys could now just barely put their fingers all the way around their cock if they put the tips of both forefingers together on one side, and the tips of both thumbs on the other. Stroking off was now a two-handed job. Many guys could lick the tip of their erect cock by simply sticking out their tongue because it reached to or just below their chin when hard... and everyone could get hard. Everyone knew sex was going to have to be different now, and a lot of men were initially afraid to try fucking. It was very upsetting: how the hell was a cock that massive going to fit into anything? But, as with anything sexual, a few adventurous souls had to know and gave it a shot.
The graphic designer had been a rather portly man, and consequently underwent all the transformations quite quickly because his weight gave his nanobots plenty to work with. First he had filled out a nice big his cock nicely, then his weight transformed into muscle leaving him looking much like a competitive bodybuilder muscle-god type would have before GID, and then when Phase 4 hit he found himself the proud carrier of a 20.5 inch cock... about six and a half inches larger than he had ever imagined a cock could possibly be, and far thicker. It was... upsetting.
It was morning, and he was at the gym, which had become the defacto mens meeting place and sex club for his part of town. He was in the crowd in the workout room where most of the guys had settled down to be together through the latest round of alterations to their bodies. The previous changes had been fun, but this one was scary. The earlier jubilation that cocks were getting larger quickly gave way when it became clear that they were going to be too large for most conventional sex to take place. Men were sitting around nude, staring in shock at their absurdly massive dicks, or holding the massive meat in their arms and crying. Some were blubbering about how much they would miss fucking, or getting fucked, or sucking cock, or getting deep throated. Everyone was upset enough that actual sex, even stroking off, had ceased for a few hours and the only contact going on had been men hugging and comforting each other.
The graphic designer was as stunned as the rest, but a bit better at restraining his expression than most of the rest, so he appeared to the others to be sitting contemplatively instead of freaking out. A college freshman seated very near him noticed his apparent composure and made a decision. Crawling over to the graphic designer, he started licking the head of the designer's monsterous cock. The designer was obviously a bit surprised, so the student decided to explain. "I want you to try to fuck me," he said, "so I need to get you hard first."
In a bit of a daze, all the designer could say was "oh." He could't figure out how the heck it would happen but he could at least try to enjoy the oral attention and see if he could shake himself of the shock.
Enjoying it became a bit easier as a few other surrounding men decided to join in the licking. With six mouths avidly drooling on and licking at his cock, the sheer sensations rapidly hardened it into a giant ramrod. Soon the college student moved to position the head of the designer's Cock at his ass, and the designer prepared himself for some uncomfortable pressure and the disappointment of the student. But, to everyone's surprise and delight, the cock head slipped right into the student's ass and just kept going. Had their asses been loosened to accommodate? Apparently... soon the designer's Cock was buried deep, deep inside the student and they stared in surprise into each other's eyes as they sat more or less face to face with their arms and legs wrapped around each other.
And then, it happened. Softly at first, but rapidly growing in strength, the designer felt the inside of the student's body send waves of hot, moist massage rolling up and down the length of his massive shaft. It was as if a tight, hot, wet, giant mouth was giving him the world's largest blowjob as the new chamber of the student's converted ass flexed hundreds of tiny muscles in sequence while releasing a thin layer of lubricating liquid to pleasure him. It was, bar none, the most intense pleasure he had ever felt, and he was gasping and panting with delight.
To the student, it was slightly different. He felt every inch of the absurdly expansive member lodged inside him and was filled up by it. The throbbing of the massaging action of his ass felt to him as if he was being fucked by the giant cock even as he sat still, sending waves of pleasure through the very core of his being. He felt utterly fulfilled, as if for the first time in his life he was truly complete - completed by the man with the massive cock who had for the moment become one with him. He felt so overjoyed by it that tears of joy streamed down his face as he passionately kissed the designer, pressing his own throbbing pole between them as they embraced.
The onlookers stared in amazement at the couple as they writhed and moaned in joy. Soon someone hesitantly produced a bottle of poppers and placed it under the student's nose. As the student inhaled, he felt the bottom drop out of his mind as the pounding and pressure of poppers rapidly filled his head. As the onlooker gave the designer a short, he too lost control and his mind. The two of them had had little enough idea what was happening to them before they got high, and now they had no ideas of anything at all, and the intensity of the pleasure increased to the level that they both felt constantly on the edge of the biggest orgasm of their life.
The next eight hours were a blur of sexual ecstacy filled with the intense feelings of the designer's cock and the student's ass, the designer's massive musclebound torso, the student's boyish face, the pounding of poppers in their heads from hit after hit from the brown bottle, the student's cock pressed between them, and the occasional slight dribble of precum from its head, which now tasted to the two better than anything they had ever eaten or drank. At the end, they both shot loads of cum larger than anything ever seen before. Deep inside the student it immediately began to be absorbed by his ass, while the designer was overcome by desire for the scent of the student's load and joined him in lapping it up. The cum filled each of them with a feeling of utter satisfaction and contentment as they came down from the drugged stupor of the poppers.
Some of the others were immediately choosing a partner to try the New Fucking with. Others were frightened and needed to adjust to the idea before trying it. But, they and others like them who had witnessed similar adventurous scenes - seen the world over in other gyms, private homes, school locker rooms, parks, even Times Square - spread the word that the new Cocks were not useless, and sex was changed forever.
Medical researchers had determined that GID was caused by an artificial self-replicating nanobot, but gave up trying to figure out how it worked and whether or not they should try to stop it when the bodily changes of Phase 4 forced them to drop everything to study the new bodily structures. The Cock was a very obvious change, but the internal changes were more severe as organs had been slightly rearranged to make room for the massive cock massage sheath inside the ass. The colon was no longer, as the nanobots were now using any excess material from the digestive tract to replicate and as energy to repair large physical problems with the body... such as correcting pulled muscles, broken or weakened bones, blindness, even paralysis. Any leftover material was used to replicate nanobots which would then leave the body. The ass was now strictly a pleasure organ as it was no longer needed for other purposes.
It was a good thing the birth rate had dropped, because with all the medical benefits of GID there were a lot more healthy (and horny) people suddenly walking around who otherwise were dying or would have already died. However, the birth rate was dropping off to essentially zero as women who were already pregnant gave birth, men were no longer having sex with them, and women, all lesbians now, wanted nothing to do with those ridiculously large cocks anyway. Governments and the United Nations formed study groups to examine the problem and recommend both cultural and technical solutions for perpetuating the species.
Women, as a group, were upset that they'd had to keep the businesses of the world going more or less without male help for two or three days as men underwent Phase 4, had New Sex like maniacs, and got over the initial shock and novelty, but the Engineer had compensated them with eternally youthful breasts as his gift for Phase 4, so the complaints were not too vehiment.
The only men left on Earth who had not yet been Converted by GID were a remote tribe of native Brazilians who lived deep in the rainforest and only had contact with conventional civilization about every six months. They were in for quite a surprise when they eventually came across a team of nature photographers, contracted GID, and underwent all four phases of transformation within a day. Their cocks grew so fast the growth was visible... and this, of course, became what happened to boys as they reached puberty.
Fashion designers and clothing manufacturers found themselves in a brief boom as new menswear had to be designed to accommodate the giant new cocks. Nobody's pants even remotely fit after Phase 4 hit, and the Cocks didn't really fit in regular pants anyway. It couldn't be left to just dangle, as it tended to trip up the feet if not outright dragging on the floor when it wasn't hard. Various solutions were tried ranging from jumpsuits with internal straps to hold the cock up along the chest, to pants with a third leg. Ultimately the popular solution became that when it was warm enough and an appropriately casual situation, men would simply wear it hanging out through a hole in the front of their pants, draped over a sort of sling arrangement in the front of their shirt. In cold weather, insultated jumpsuits were the outfit of choice.
And back in the Engineer's loft, the engineer wasn't in. He was in Central Park, in the middle of a circle of one thousand men, each with his cock in the ass of the man in front of him and his ass clamped on the cock of the man behind him, as a public expression of the new male sexuality. He'd get to thinking about his creation another day. Today he, like the other 999 men and most men everywhere, were too filled with cock, poppers, and pleasure to care.