Remember, if the time should come when you have to make a choice between what is right and what is easy, remember what happened to a boy who was good… - J.K. Rowling

Harry — I think I've just understood something! I've got to go to the library!”
And she sprinted away, up the stairs.
“What does she understand?” said Harry distractedly, still looking around, trying to tell where the voice had come from.
“Loads more than I do,” said Ron, shaking his head.
“But why’s she got to go to the library?”
“Because that’s what Hermione does,” said Ron, shrugging. “When in doubt, go to the library.

"Can't stay long, Mother," he said. "I'm up front, the prefects have got two compartments to themselves-"
"Oh, are you a prefect, Percy?" said one of the twins, with an air of great surprise. "You should have said something, we had no idea."
"Hang on, I think I remember him saying something about it," said the other twin. "Once-"
"Or twice-"
"A minute-"
"All summer-"
"Oh, shut up," said Percy the Prefect.

Hermione's white face was sticking out from behind a tree.