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Colin Creevey is a Gryffindor first year. He is also a Muggle-born. He is incredibly enthusiastic about the wizarding world, and his constant questions for Harry give J.K. Rowling a chance to refresh her reader's memories about the rules of Quidditch and the facts of Harry's life.
Colin is a diehard fan of Harry's. He follows him every chance he gets while trying to snap photographs. Harry finds him a bit irritating, actually. Ernie Macmillan offers up the fact that Colin is both annoying and a Muggle-born as proof of why Harry Petrified him. Of course, Ernie is completely wrong – but the circumstantial evidence against Harry looks unfortunately convincing.