"Well, at least you're human again." Katie said, her friend shaking in her new body. Tiffany, Tony now, stares at his body. He runs strong hands over his chest and torso. Then looks at his penis, an impressive ten inches flaccid.
"I guess this isn't so bad." he said, surprising himself with his transformed voice.
"Do you want to try another one?" Katie asked.
"Uh... I don't know. What if those turn me back into an animal thing?" Tony asked nervously. He was still inspecting his body, turning around to look at his legs and well molded ass. He was pretty hot, if that wasn't too vain of him to think.
"I'd totally date me if I was still a girl." he thought.
"Tiff?" Katie asked, her friend completely absorbed in his own body.
"Oh, sorry. What do you think that one does? And maybe you should start calling me Tony if we can't find a cure." Tony said.
"Tony? Really. All the cool, sexy names in the world you pick that one?" Katie asked, smiling.
"I like it." Tony shrugged. Katie finds the motion extremely attractive, but she looks at the table to stop herself from getting aroused.
"Well... the red one made me sort of normal. The blue one turned you into a dude. Maybe this clear one will work." she said. She took one of the empty vials, and poured half into it.
"Bottoms up?" Katie said, holding out the vial. She and Tony gave each other weak smiles before clinking the vials, and downing their portions in one gulp.
Another warmth raced through their body. Tony's muscles began to bulge, and grow. Before he had a well toned body, now he looked more like a body builder. His biceps looked like they were stuffed with footballs, as did his thighs. The already thick bush around his genitals spreads out. The hairs creep down the sides of his thighs, and around his asshole.
Meanwhile, Katie's having a different transformation. Her male genitals swell and grow outward. Her cock was only ten inches soft before, but now it didn't seem like it was ever going to stop growing. Her nuts tugged down until they rested on the floor. The head of her penis hits the ground, and then snakes forward. And just when things seems to be ending, Katie's breasts quiver and push outward. They grow until they hang down on her chest. She doubles over, the weight too much for her. Her engorged nipples, now the size of soda cans, brush against the cold basement floor.
"Oh fuck!" Katie said, an erection returning. Her three foot penis becomes stiff, and when it finally stops growing it's at least six feet long, and as wide as a roll of toilet paper. Her balls heave, about the size of a medium pumpkin. Her breasts, too large to be measured by cup sizes anymore, once again begin to leak milk.
"Katie!" Tony says in a panic. He didn't know what to do. The only remaining vial, the green one, stared at him. Katie lay on the floor, shaking with her building orgasm.
"Oh god, what do I do? She only took half of the vial too!" Tony thought. Katie moaned as her small hands were lost in the mess of body parts as she tried to masturbate. But the only thing she could do was writhe on the floor to get the necessary stimulation she needed.
Katie was on the verge of release when Tony made the last second decision to pour the green liquid down her friend's throat.