Ron: What do they think they're doing?? Keeping a thing like that locked up in a school. Hermione: You don't use your eyes, do you? Didn't you see what it was standing on? Ron: I wasn't looking at its feet! I was a bit preoccupied with its heads. Or maybe you didn't notice, there were three! Hermione: It was standing on a trap door. Which means it wasn't there by accident. It's guarding something. Harry: Guarding something? Hermione: That's right.