Severus Snape

Severus Snape is a fictional character in the Harry Potter series of novels by J. K. Rowling. In the first five novels, he is the professor of Potions at Hogwarts School of Witchcraft and Wizardry. In the sixth book, he teaches Defence Against the Dark Arts, and in the seventh book he ascends to the position of headmaster before his death. Snape is hostile, yet heroic towards Harry Potter throughout the series; Harry eventually learns that Snape was bullied by Harry's father, James Potter, and was in love with Harry's mother, Lily Evans. This causes Snape to have mixed feelings towards Harry, who resembles his father greatly, but has his mother's eyes.

As the series progresses, Snape's character becomes more layered and enigmatic. A central mystery is unravelled concerning his loyalties. Snape dies at the hands of Lord Voldemort in the seventh book, at which time his back story is revealed. Despite his attraction to the Dark Arts and Voldemort's ideology of wizard supremacy, Snape's love for Muggle-born Lily Evans, Harry's mother, eventually compelled him to defect from the Death Eaters. He then became a double agent for Albus Dumbledore and the Order of the Phoenix. The fact that Lily chose James Potter, Harry's father, only fuels Snape's hostility towards Harry.