Hagrid

Rubeus Hagrid is a fictional character in the Harry Potter book series written by J. K. Rowling. The character is usually addressed only by his surname. Hagrid is the Keeper of Keys and Grounds, the gamekeeper and, starting in Harry's third year at Hogwarts School of Witchcraft and Wizardry, the Care of Magical Creatures teacher there. Later in the series, it is revealed that Hagrid is also a member of the Order of the Phoenix. Hagrid was the first member of the Hogwarts staff to be introduced to Harry before he began attending the school. He was also one of the first characters to imply that the idea of thinking of wizards as "pure-bloods" and "half-bloods" is a dated concept.
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Keeper of Keys and Grounds and teacher of Care of Magical Creatures class at Hogwarts from Harry's third year. He was a student at Hogwarts but was expelled for unknown reasons. Professor Dumbledore allowed Hagrid to stay
as gamekeeper. Hagrid is almost twice a tall as any other person and seems five times as wide. He has masses of bushy, black hair and a huge tangled beard. Has a liking for strange and dangerous creatures - especially dragons.