The black boy, Neville, and Hermione all had surprised looks, but they were different sorts of surprise. The black boy looked at his two companions as though they'd suddenly revealed they belonged to a strange cult. Neville looked at Harry as though he hadn't really seen him before; apparently he didn't realize which "Harry" he was being hastily introduced to. Hermione looked like she'd handed in an essay and only then remembered she'd meant to add a paragraph in the middle.