The groin feels tight as an erection occurs. The canine teeth grow longer into fangs. "What the hell is happening to me." He says in a younger voice." For the serum was causing him to get younger. And was shaping his body tone to a mid twenty year old to a seventeen year olds body. For his shirt was getting tighter and his abbes were getting more defined, along with his chest as the white fur enveloped his front side. Tearing his shirt off. Then covering his back and arms with orange fur with blank strips like his legs. His feet were getting sore in his shoes as his toes were getting numb. He held his left hand over his face to watch it and the other hand grow black pads and sharp claw's emerge from the finger tips. Right when when three taloned toes tore threw his shoes and elongated to tiger paws. He had to lean on the wall for support. To get used to standing on the balls of his feet and toes. And he felt his ears got pointy and shifted with his head as became a tigers short muzzle, filled with carnivorous teeth. His screaming turned into a roar as he opened his eyes to a golden greenish color, which used to be a light blue. Since his brain became a tigers he forgot a majority of his life and what he learned in school. That became replaced with heightened tiger scenes such as hearing and the foul smell of Joey near him watching his agony. Inside his pants his teen hormones mixed with a tigers giving unsurpassed results as he begun to realize he needed a mate. As his manhood was wrapped into a sheath. There was a pull at the end of his spine as he franticly tried to take off the Rumanian's of his pants and undies around his groin. As he maneged to pulled them off a tail came out of his butt and grew down to his ankles. As his hips merged with his butt he fell on all fours. His back bone arched itself to give him a more thicker neck and broadened his shoulders. Both his legs and arms gained more mass as well but shrank a little. Then his abbes quickly gained more mass to accommodate his widening chest and ribcage to house the new shifting organs. As he layout there he panted to calm down. Joey was laughing success!