Severus Snape

Alan Rickman as "Severus Snape"

Severus Snape is a fictional character in the Harry Potter book series written by J.K. Rowling. Snape primarily teaches Potions at Hogwarts, though in the sixth novel he teaches Defence Against the Dark Arts. He wears black, flowing robes which give him the appearance of "an overgrown bat".

Snape is generally depicted as being cold, calculating, precise, sarcastic,

and bitter.

Snape is the only protagonist who genuinely had a choice to make and struggled to do the right thing, hence the only one to face a "compelling inner crisis". Snape leaves Harry his dying thoughts (to be viewed in the Pensieve) and ultimately reveals to Harry that he had been loyal to Albus Dumbledore throughout the series. Snape's fierce devotion to and love of his childhood friend (Harry's mother), is the foundation of that loyalty.