Who is Trustworthy?

When Jon got home, he went quickly to his room. Though he had hidden it pretty well at school, he was upset at Karyn. Even though she was his best friend, and even though he had warned her to be careful, she had still made a careless wish! Thinking about it, Jon decided that he needed to make Karyn more responsible, or else make her forget it altogether. But if he made her forget about the stone, he wouldn't have anyone to share the stone with, and he wanted to have fun with someone else, not just by himself. In the end, Jon decided to...