Jon braced himself, waiting for the stone grow warm in his hand. But nothing happened. Fortunately for him, the stone had pretty strict rules. Karyn said the words "I just wish", not "I wish". Having the word "just" in there stopped it from being a wish that could be granted by the stone.
Jon yanked his hand back from Karyn and quickly put the stone in his pocket. He dodged a bullet and he didn't want to take the chance to dodge any more. But his sudden withdrawal from Karyn may have given her the wrong signal. He really did want to date her, but yanking away from her like that might have made it seem like he didn't, even though he made it clear moments earlier that he did.
