Hogwarts staff of the Marauder's Map (the Weasley twins, Harry, Ron and Hermione), and Voldemort himself. He tends to favor almost sadistically harsh punishments, and gleefully allies himself with Umbridge when she prescribes such punishments on students. He has an obsessive dislike of mud, animate toys, and all other things that might interfere with his desire for an immaculately clean and orderly Hogwarts. He is also portrayed as having a constant antagonism towards Peeves the poltergeist and often tells Dumbledore that Peeves should be thrown out of Hogwarts. He also likes to wander Hogwarts corridors at night, presumably in the hope of
Hogwarts staff However, in the American edition of "Half-Blood Prince", it is re-spelled as "Sybill", matching the UK edition. Professor Trelawney is portrayed by Emma Thompson in the "Prisoner of Azkaban", "Order of the Phoenix", and "Deathly Hallows Part 2". Hogwarts houses at least twenty ghosts, but when people in the novels speak of the ghosts at Hogwarts they usually refer to one of the four resident ghosts of the Hogwarts houses: Sir Nicholas de Mimsy-Porpington (or, as the students refer to him, Nearly Headless Nick), the almost beheaded ghost of Gryffindor house; the Bloody Baron, who is the ghost of Slytherin