The following fictional characters are staff members and denizens of Hogwarts in the Harry Potter books written by J. K. Rowling. The staff and their positions Teachers and staff members The following teachers and staff members do not have their own articles or are not listed in other articles. Argus Filch Argus Filch is the caretaker of Hogwarts. While he is not an evil character, he is ill-tempered, which makes him unpopular with the student body, and occasionally causes tension or exasperation with teachers and other staff. His knowledge of the secrets and short-cuts of the castle is almost unparalleled, except perhaps by the users of the Marauder's Map (the Weasley twins, Harry, Ron and Hermione), and Voldemort himself. He tends to favour 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 catching a student out of bed. Filch is revealed to be a Squib in Harry Potter and the Chamber of Secrets when Harry accidentally discovers that he is trying to teach himself basic magic from a Kwikspell correspondence course. Nonetheless, Filch is at least able to use wizarding devices that have their own innate magic, such as the Secrecy Sensor used in Harry Potter and the Half-Blood Prince. It is hinted that his dislike of students may stem from his disappointment and jealousy at not being able to do magic. In Harry Potter and the Deathly Hallows, the final book, when the school starts preparing itself for the Battle of Hogwarts, Filch is seen yelling that students are out of bed. He is later seen overseeing the evacuation of younger students. Filch has a cat named Mrs Norris to whom he has a particular and possessive attachment. She acts as a hallway monitor or spy for Filch. If she observes students engaging in suspicious activity or out of bed after curfew, she finds Filch and he arrives in seconds. She has been known to follow Hagrid everywhere he goes in the school, apparently under Filch's