"I thought maybe we could trade something that the other sex has," Karyn said. "You know, like swap chests. You can have my cleavage. Or maybe we can swap genitals, hair ... I could even loan you my womb. I'd love to have sex without worrying about having a baby."
Jon thought for a moment, then said "Only if we do it with a time limit. I'm not playing for keeps."
"Alrighty then," Karyn said.
Jon held the stone in his hand, then said "I wish that for the next seven days, Karyn and I would have our sexual preferences swapped." The stone glowed, granting his wish.
"Sexual preferences?" Karyn asked.
"Yeah," Jon said, then he smiled. "What do you think of Sarah McMillan?"
"She's a total bitch. But, wow, what a hot body. You know, I'd love to ..." Karyn's eyes went wide. "I can't believe I just said that." She thought for a moment. "I ... I'm actually attracted to her."
"See? That's how I felt about her. I mean, yeah, she's a total bitch, but ..." Jon thought for a moment. Something was wrong. He didn't find her attractive anymore. But then he realized that was because of his wish.
Karyn saw the confused expression on Jon's face, so she asked him "What do you think of Biff Meadows?" Biff was captain of the football team and Sarah's boyfriend.
"What do I think of him? Well, he's kind of a jerk, and a bully. But, man, what a body. I bet his cock is ..." Jon had to stop himself. "Oh my god. I'm gay."
"We're both gay, Jon. Isn't that what you thought would happen after you made your wish? At least it'll only last a week and not forever."