Newt's eyes went a little wide when she said wizard, but then he only looked pleased, gripping the case a bit harder and his expression turning into something like a smile (but a rather awkward version of one). "Oh good, you're not a muggle," he said. "I had an awful experience recently when I failed to obliviate one. Well, I suppose it turned out all right in the end, made a new friend, even, though, well, I suppose his memory is gone again..." His voice trailed off. He'd forgotten he was supposed to guess.