Something that turns me on is a woman half undressed, with clothing still on but exposing herself. There's just something about it. Clothing can be sexy, and a naked body of course, but clothes disheveled and half on, either torn or not quite off yet, is really sexy to me. Like, a shirt pulled down to expose the breasts, or a strap from a bra or tank top hanging limply off the shoulder, or panties taken off and left to gather at the knees or loosely around an ankle.
Sometimes, clothes are like a mask we wear to show the world and there is something to be said for an outfit that accentuates curves, with colors and soft textures. And a naked body presents a kind of vulnerability, a readiness to be taken, no more barriers between flesh. But the in between is like a mixture of them, the mask still there, who she is with it on, still there, roughly tugging it away from those essential parts of the body to escape the barriers it puts between us. Also...it's just sexy.
Also, markings left in the heat of passion(on either me or her), like bruises, scratches, and bite marks. Just something about letting go during intercourse, to the point where your partner, as an object of desire, becomes something more--a canvas of violent intimacy. Seeing things like, a bite mark embedded in her shoulder; feeling scratches left on my back; seeing bruises on her wrists where I held her down; hickeys left on her inner thighs--all heat my blood.