Hermione buys Crookshanks before she returns to Hogwarts for her third year. She buys Crookshanks in a animalstore in the Diagonally. Crookshanks has hunt on Scaffers at Hermione's third year. This is the reason for the lot of fights between Ron and Hermione in this year. But at at the end of the year it is al right between them.

Crookshank's vatch is thick and he has o-legs.