"I wish ..." Jon said, with a smile. "... that Karyn was naked and in my bedroom and desperately wanted to make love to me." Jon had been friends with Karyn since they were in grade school, but more recently, he had developed feelings for her that she obviously didn't have for him. But now, all of that would change.
The stone glowed, causing Karyn to appear in his room just as he wished. But since his wish was one that caused unethical harm to Karyn's mind (making her love Jon, in other words), Jon would be forced to have bad luck for the next one hour.