I'm hoping that you know what I'm talking about with S&M relationships; the Sadist, the dominant one, likes to hurt people (physically) while the Masochist, the submissive one, likes to get hurt (physically). Having those two together would balance each other and put them into compatibility. Get it?
In my opinion, if I were to ever be in an S&M relationship, I would be the S. I just love the pleasure of seeing guys in pain (physically). Real life or Fictional, I like seeing either get hurt.