Once they'd swallowed the contents of the vials, Alex and Hugo got off of Chris and Mike. Mike stood up by himself, Hugo grabbed Chris under the arms and lifted him to his feet. Both of them started to tense.
John watched as the first, most subtle changes began. Chris kept adjusting his jaw, as though he was trying to pop his ears, but as he did so, his lower mandible was visibly growing. It overtook his upper teeth, giving him a prominent under bite. The canines were the first to appear, poking out from between his lips. The next teeth back soon followed and both sets grew until he had canine tusks that reached nearly to his eye level.
Mike's transformation began lower. Almost imperceptible at first, his shoulders and chest began to broaden. The front of his shirt showed the strain as his security uniform was pulled in both directions, the white of his undershirt showing between buttons. Finally, one button flew off, then the next, then what few remained blasted off his torso, leaving a dangerously over-stretched white T-shirt behind.
Hugo seemed to be enjoying himself. He had retreated to a corner of the room, and was stroking his cock as he watched. Alex seemed more torn as he witnessed the changing men before him. Beast man or not, his expression was unreadable.
Chris's change stayed near his face. His brow sloped downward and stubble covered his widening jaw. His neck followed, widening as the stubble shot down toward his chest. Mike was beginning to look a little top heavy. His chest was almost three feet across now, straining an otherwise loose T-shirt, but his legs were unchanged and his arms were only beginning to shift.
Seemingly with the same thought, both Chris and Mike grabbed the fronts of their shirts and tore them off nearly simultaneously. Chris's black wifebeater no longer obscured the progress of the hair as it spread down his neck, exploded from the center of his chest up toward his shoulders, down his stomach, over his arms and across his back. Muscle followed it, building his chest, his shoulders, his arms and down his newly tight, rocky stomach. Strong, but lithe, his chest and arms were nearly devoid of body fat and showed off every striation, or at least would have if not for the dense, curly hair that covered nearly every part of him. Mike, on the other hand, was huge. He was far less hairy: he had a small thatch in the center of his chest that faded to down toward his nipples and barely traced down his stomach, but he was huge. Mike didn't have the cut his brother did, but his body was solid as a rock. His abs were hidden, but his stomach was flat and hard. His biceps, chest, back, all of it defied human anatomy in terms of sheer size. His was a body that would stop a truck in its tracks.
Mike was the first to rip off his pants. His legs were starting to look like the rest of him; huge, meaty, and powerful. His cock began at a modest size, but that was changing rapidly. It gained width, first. It quickly ballooned to the dimensions of a beer can, then surpassed them. The edge of his cock head flared beyond the line of his shaft by a quarter inch at least. Mike's head was thrown back, he was panting, as his dick expanded until it was as wide around as a wine bottle. It hadn't gained much length, measuring about seven inches, but it looked capable of doing serious damage. His sack, which by this point looked comically small, followed the lead of his cock. It forced him to shift to a bow-legged stance, lest his massive thighs crush it. His nuts expanded to the size of eggs, carried snugly in a sack that was stretched very thin to contain them. They almost visibly churned as his hard-on raged.
Chris had actually been watching his brother's ordeal throughout until he hastily ripped off his belt and forced his pants down. His cock was already hard, and it was getting harder. It, too, looked appropriate to its owner, as it stretched further and further from the wild jungle of his pubes. Veins throbbed along its length. It came to rest at just short of eleven inches and curved lazily upward, almost level with where his navel lie behind all the fur that covered his stomach. His balls, though much less massive than Mike's, hung nearly midway to his knees.
The transformation slowed as smaller changes took place. Chris's fingers grew longer and his nails grew sharp and from the sound from his boots, the same was true of his toes. Mike's skin grew thicker and his brow drew lower on his face. Both men's hair lengthened, and their posture moved forward. And before John could tell if the transformation had truly finished, the new beast men tackled the beta that had been restraining them earlier. Chris was on Hugo, though he nearly tripped over the pants still around his ankles. Hugo looked only lightly hairy when compared to Chris, and they had trouble, at first, trying to mash their faces together with Chris's tusks in the way. Alex and Mike were a strange combination. Alex's impossibly long arms and legs wrapped around the impossibly wide Mike. The air in the room grew heavy and damp with the exertions of its occupants. John, once again sporting damp pants, was painfully erect. However, he realized that if he tried to involve himself in the wild fucking taking place, he'd be lucky to survive it. He quietly opened the door behind him, and stepped into the cool morning air.