There's a ton of things that turn me on during sex, but the thing that I'm currently looking for is a girl to scratch the shit out of me. I want her to rake her nails across my back until I bleed. I want to wake up in the morning and not be able to put my arms in front of me because the stretching will rip the scabs. That's what I want. And a little biting wouldn't hurt either.
As one girl told my roomate: "There is no pleasure without pain."