His name is Sebastian Herb. He has thius gnarly demonic goopy sarm that has a mind of it's own. Everyone knows he hasn't had it since birth, but nobody remembers WHEN he got it or how, it just kind of is there now. He can't control the arm, biut he can mentally suggest things for it to do. It doesn't and Sebastian knows it's ignoring him on piurpose. Sebastian has become very good at dodgingthings by living with the arm. His greatest fear is breaking his regular arm and having to rely on the goopy one.