Unknown to the six frat brothers in that room, the Contagion evolved Tristan's pheromones further, making it pleasurable to Tristan to release them and adding a special effect to the pheromones.
Swallowing every last drop of Tristan's cum, Greg pulled back and looked up at Tristan, who was panting with head against the back of the couch. There was a glint of lust in Greg's eyes as he looked Tristan up and down, clearly admiring the sexy body in front of him that he had ignored for so long.
"You're so hot," Greg moaned. "Your body is sooo hot. I wish all of us in this room could be a part of you." And that's when the special effect of the pheromones kicked in.
Tristan moaned loudly as he started to release his pheromones. The pheromones reached the nose of each of the other five brothers in the living room. They all moaned in response and immediately became immensely attracted to one of the appendages sticking out of Tristan's main body. Greg became re-obsessed with Tristan's dick. Raymond, who was seated to Tristan's immediate left, found Tristan's left arm overwhelmingly attractive. The same could be said with Ethan with Tristan's left leg, Karl with Tristan's right leg, and Sean with Tristan's right arm. They all stood up, including Tristan, and immediately felt an urge to strip naked. After doing so, Tristan felt waves of pleasure hit him again and sunk to the floor, sprawling himself across the wooden floor and allowing the others to have their way with him.
They each began to either lick, kiss, or suck their respective body parts of obsession, moaning with pleasure. The more they touched Tristan's body parts, the more prevalent a newly emerging ache in their asses, an ache to be filled. None of them were concerned if someone was going to interrupt them. If someone had entered the room, the air was so thick of pheromones that anyone would immediately forget about anything else and either find something to fuck or start jacking off.
Sean was the first to act on the ache. He moved his tongue all around Tristan's right arm, ending at his fingertips. Sensually grabbing Tristan's hand, he rotated his body and promptly stuck Tristan's hand in his asshole, nearly screaming in pleasure. Then, slowly but surely, he began to push more of Tristan's arm into his asshole. It wasn't until he reached Tristan's elbow that Sean's legs and feet fused together, losing all of his toes. But Sean kept pushing. Sean's ass began to migrate down his fused legs until, when he had reached Tristan's shoulder, his ass was at the end of his fused legs, or just leg now. His dick began to shrink as his leg began to build up with muscle, but not leg muscle. Sean was enjoying the pleasure he felt and raised his torso up with his arms. The muscle on top of his leg bulged. Sean moaned with passion at the realization that he was becoming Tristan's arm! He laid down and hugged his torso, his arms melding into it and disappearing altogether. The muscles in his torso rearranged to become very strong forearm muscles. That meant his head was going to be the hand! He grinned goofily as his teeth pulled back in and stuck his tongue out, no longer able to keep it inside his mouth. He looked at Tristan's face for the last time before closing his eyes. They fused shut as his skull rearranged and filled the eye-sockets. His hair fell out. His nose split, both halves filling up with bones. His ear-holes sealed shut while his lobes became long and with a rounded point. His tongue migrated to the bottom left corner of his face to become the thumb. In the matter of five minutes, Sean was now Tristan's very muscular arm.
The same things happened to the other guys; Ethan and Karl becoming Tristan's legs, and Raymond becoming Tristan's left arm. Something different happened to Greg, however.
Greg had already both Tristan's entire dick and Tristan's balls. His legs curled up on themselves and became an orange sized nutsack, the hair and muscles becoming testosterone for Tristan's new balls. Greg's dick, instead of shrinking, lengthened and widened until it was twice the length and width of Tristan's old dick. Greg leaned his back into Tristan's torso, which was now relatively underdeveloped compared to his bodybuilder-sized limbs. Now, Greg was a very built guy, having wrestled all throughout high school. Greg's head sunk into his shoulders and disappeared. His arms fused into the sides of Tristan's torso. The boundary between the two torsos faded as Greg's torso sunk into Tristan's, but not completely.
The pleasure increased as Tristan released even more pheromones. The pheromones made their way out through the windows and into the world. Now, because of Greg's wish, Greg, Karl, Raymond, Sean, and Ethan are part of Tristan's body. No one has any recollection of who those five were. Their families no longer recognize the names, and all possessions owned by those five are non-existent. Even the name Tristan won't ring a bell to anyone in the frat house. He is now Michael, the bodybuilder of the fraternity. The clothes that lay around him dissolve into thin air as new clothes appeared on Michael's body. It now looked as if he had taken a nap on the soft carpet that he had installed into the frat house.
Unknown to Michael, he still had the Contagion on him, but it was done changing him. It gave him the ability to grant any wishes that he hears like a knee-jerk reaction, even when he's asleep. It also left him with very potent pheromones that would make anyone he flirts with have no choice but to flirt back and to accept his advances.
The front door opened, and the new reality began as Brock walked in and saw Michael lying on the ground, fast asleep with a huge boner.
"Must be having a good dream," Brock said, more to himself than to Michael. He then was a little frustrated that Michael could get away with things like sleeping in the middle of the floor of the living room or "forgetting" to do his share of the upkeep of the house.
"He has it so easy," Brock grumbled, scowling at Michael's sleeping form. "I wish..."