First things that come to mind are having a good sense of humor and not taking himself too seriously, having an open mind that is dirty. A dirty mouth lol. It depends on who it is though different people are great in different ways and I don't really have a specific type.
Ok, I don't follow celebrities very much, so this will be based more on the characters I seen then play than themselves:
M = Gillian, F = Charlize, K = Jennifer