Okay, that smile didn't bode well at all. Harry found himself getting the sinking feeling that this wasn't going to be the first time this student would find her way into his office. He'd have to start moving things into his own room. And from what she said, take into consideration some other precautions. Of the things she did take from him, it was likely that Bob was one of the most valuable, but also one of the least dangerous.
"Right," he said in response, "And I take it your unique ability isn't something you're going to tell me about." Of course. Why would a student actually give him a straight answer when there was mischief to be had?