Remus Lupin is the Defence Against the Dark Arts teacher during Harry’s third year at Hogwarts, the year when Harry discovers Sirius Black is his Godfather. It is revealed that Remus Lupin was one of Harry’s father’s best friends, alongside Sirius Black and Peter Pettigrew. Remus is a werewolf, who becomes very dangerous during the full moon. He keeps this as a secret from his students, but is not missed by Hermione Granger, who has worked out his werewolf condition. Remus Lupin looks out for Harry and is very protective of him. He later goes on to marry Nymphadora Tonks, the Auror.