Hermione Jean Granger is a fictional character in J. K. Rowling's Harry Potter series. She first appears in Harry Potter and the Philosopher's Stone, as a new student on her way to Hogwarts. After Harry and Ron save her from a mountain troll in the girls' toilets, she becomes best friends with them and often uses her quick wit, deft recall, and encyclopaedic knowledge to help them. Rowling has stated that Hermione resembles herself at a younger age, with her insecurity and fear of failure. The character has received immense acclaim and popularity, and was voted the best female film character in a poll conducted amongst Hollywood professionals by The Hollywood Reporter in 2016.

From the third book to the sixth, Crookshanks is Hermione Granger's pet cat. Crookshanks was purchased by Hermione in a shop called Magical Menagerie in the third Harry Potter book; Harry Potter and The Prisoner Of Azkaban. Crookshanks resembles a Persian Cat, and Rowling has described him as half-Kneazle, an intelligent cat-like creature sensitive to dishonesty, explaining his identification of the rat 'Scabbers' as Peter Pettigrew, and of Sirius Black in his dog form. Crookshanks is seen in Prisoner of Azkaban talking to Padfoot in the school grounds. Crookshanks was portrayed by a cat called Crackerjack.

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