Marcus Flint

Marcus Flint (born c. 1985) was a student at Hogwarts who was sorted into Slytherin House. He was the Slytherin Quidditch Captain and a Chaser in the first three books.

Flint was stated to be a sixth year in Harry Potter and the Philosopher's Stone, yet he was still at the school in Harry Potter and the Prisoner of Azkaban. J. K. Rowling has explained this by saying that he had to do a year over again. This explanation does not deter some fans from calling other consistency errors "Flints", however.