"I wish I didn't have a penis this small." Jon said, finally.
Jon stood perfectly still for a moment, wearing nothing but his underwear, waiting for something to happen. Soon a warm feeling began to emanate from his crotch. He looked down to see his member glowing brightly underneath his briefs and wriggling furiously of its own accord.
"It's working," Jon smiled. "It's going to grow bigger!"
As his dick writhe around, Jon felt himself starting to get a boner from his excitement. He saw his thrashing penis begin to stiffen, but then with a loud 'POP' it was over. His groin had ceased to either glow or wiggle.
"Hmm, is that it?" Jon wondered as he moved his hand to his penis, "It doesn't look any bigger. In fact it looks-"
It was then that Jon's hand found that the bulge in his underwear didn't contain a penis of any size! In fact, there was nothing there now except what felt like a smooth patch of skin! It was gone! His cock was gone!!
He needed to take off his pants and check the damage. Jon pulled at his underwear and froze again. He'd felt the crotch of his briefs pull up INTO something between his legs!
Jon's hand, quivering with fear and panic, slipped into his underpants and explored his changed nether-regions. Then Jon hastily yanked down his briefs to confirm his fears - he had a vagina! He had female genitals! He didn't have a small penis anymore, but a woman's vagina instead!!
What had he done? More importantly, what could he do now!?