Dementor

Dementors are some of the foulest creatures that roam the Harry Potter universe. They are around 10-12 feet tall, and were first seen in the prisoner of Azkaban. They have a dreaded feeling like you would never, ever be happy again. The only way to get rid of a dementor is to use the charm, "Expecto Patronum." It is very hard magic, and you need to think of a very, very happy memory to do it. If you do so, it makes the dementors flee. Dementors are also guarding the prison of Azkaban. They drive most people insane there and most die in their first few months or years.

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