"I'm going to play," he told Ron and Hermione. "If I don't, all the Slytherins will think I'm just too scared to face Snape. I'll show them... it'll really wipe the smiles off their faces if we win."
"Just as long as we're not wiping you off the field," said Hermione.

Harry Potter and the Philosopher's Stone - Chapter 13 : Nicolas Flamel
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