A person who loves flirting and leading people on. They are really good at this because they are very good at changing and controlling variables in different scenarios. They "operate" the way things happen around in a way that benefits them.
Boy: Wow that girl is so hot!
Boy's Friend: You're such an operator you'll get her
Boy organizes several ways to "accidentally" on purpose meet her and be at the same place as her etc. Flirtinglike crazy all the while.