Snape is a wizard who rarely lets himself be surprised, who does not usually lose his temper or words, and who is not easily intimidated. However, when it comes to Sirius or Harry, he is much more irritable and it is common to see him with a bit of a temper. He can be: authoritarian, moody, sarcastic and resentful. But he is faithful, protective and cunning. He is the most feared professor at Hogwarts because of his strict way of teaching. He always seems moody and bitter. He's a big bully.