Guy shivered as the tingling shot down his legs, and then had to brace himself with his arms as both legs went limp. Not numb - he could feel them, but it was like the muscles had gone dead. Why was he so hot? He blinked sweat from his eays and pushed up so he cuold see what was going on. And wished he hadn't. His balls were gone!
The huge cock ended at the split of his legs, with no ball sack at all! No! He could feel them, huge and heavy, and getting bigger. But where...? Then his eyes widened. His thighs were swelling and getting soft, and below the knees his legs were shrivelling away. His legs were becoming testicles the size of watermellons!
But the changes were not stopping there. A loose fold of skin formed around his waist, and started to rise up. It covered his cock and slid higher over his belly. Guy felt his gut shift, and pulled at the rising covering with one hand. His body was rounding out, and the under what he realized was now a monster foreskin, his whole body was turning into a massive penis.
He tried to scream, but a spurt of thick white liquid shot out of his mouth. Then he fell back as his arms went limp and shrivelled up. The foreskin slid up his chest, over his shoulders, and he felt his head sinking into his neck. Vsion blurred and faded, sounds dulled. He could taste the salty gum in his mouth, which was now the slit of a huge glans.
The tingling stopped, leaving Guy feeling huge, swollen, and horney. He was a penisaurus, able to move like a giant worm, using smells and taste as his senses. He needed to find someone. Guy was dazed, his mind confused and becoming more basic, instinctual. Once he got someone, anyone, under him, he would start turning them into cum or piss.