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Professor: Transfiguration, Deputy Headmistress of Hogwarts
House: Head of Gryffindor
Professor McGonagall is one of our old favorites. She's extremely stern and stands for no nonsense, but she seems generally sympathetic towards Harry. She's also one of the three people who Stun Mad-Eye Moody/Barty Crouch, Jr. at the end of the novel. Professor McGonagall is absolutely furious that Cornelius Fudge allows a Dementor into Hogwarts, which promptly eats Barty Crouch, Jr.'s soul. This means there's no witness to Voldemort's rising except for Harry himself, whom Cornelius Fudge refuses to believe.