Cas can be described as funny, rebellious, sarcastic, and has the overall vibe of a bad boy. From what others say, Cas likes picking fights, and he is usually cold and distant with other people, except with you. He also doesn't like showcasing emotions because he feels that this will ruin his bad boy persona, and at times, he is shown to have no problem with taking human lives. Cas is very protective of people he cares about. Not much is known about Cas's background or how he became a vampire.