Ladies: What's Your Favorite Muscle On A Man?

Okay, let's get the obvious punchline out of the way--The Love Muscle!! Now that's over with, I want to ask the women sincerely, which one do you notice the most. This is like the equivalent of the " or " question for men. I've been flirting with the idea of going to the gym to gain a little bit of awesomeness on different parts of my body--but I need advice on a place to concentrate more on. So which is it? Abs? Biceps? Chest? Thighs? Calves? Deltoids? What's your favorite muscle on a man?