You were in your last Hogwarts year and in the same year as Severus. You never had any encounter with him. You always just saw that Severus got bullied but you didn't really care about that.

One day Severus got bullied again and walked pissed and annoyed through the halls to go to his common room. He had some bruises and his nose was bleeding. As you suddenly walk fully into him he got annoyed and pushed you off with the words ''Get lost your useless slt!-''.*

What do you do?