Ghosts are fictional creatures/characters from the Harry Potter Universe.They are silvery, transparent shapes looking like the people they used to be. They are able to move through walls and other solid objects, but cannot eat or hang on to solid objects. Wizards or witches become ghosts when they are too scared to move on, so choose to stay behind in the world they know. Harry is told this by Nearly Headless Nick when he is wondering why Sirius Black has not become a ghost.
There are many ghosts at Hogwarts, many of them for different houses. The Bloody Baron is the ghost of Slytherin, the Grey Lady is the ghost of Ravenclaw, Hufflepuff’s ghost is the Fat Friar, and Nearly Headless Nick (also known as Sir Nicholas de Mimsy Porpington) is the ghost of Gryffindor. Peeves is not a ghost, but the school’s poltergeist, known for causing trouble with the teachers, students, and his rivalry with Argus Filch. Moaning Myrtle is the ghost haunting the girl’s bathroom, and is very crucial to Harry Potter and the Chamber of Secrets. There are also many, many other ghosts in the school.
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