"The truth is exactly that."
"No way!" said Jeff. "You're a guy. You have to be. You look like a guy and you sound like a guy."
"It's the truth, Jeff. It's easy to prove."
"So prove it."
"I have to pull down my shorts to prove it. Would you if you had a vagina?"
"It's so unlikely that if I really wanted to convince someone, I'd have to!"
"Fine," said Jon and pulled down his shorts, revealing a complete female crotch instead of his dick and balls. "Are you satisfied?"
"Wow," said Jeff. "I guess you were right. So Jon, do you ever...."