I actually think there's two types of rough sex.
There's the hammer and tongs frantic fuck where both parties want a very physical experience, hard and fast, getting up a bit of a sweat. That could be after a slow and steady foreplay build-up, or it could be a heightened anticipation scenario, perhaps meeting someone in a bar for a couple of hours, the 'signals' going back and forth which tells both parties there's going to be a hell of a fuck at the end of the evening.
The other is actual physical blows, ranging from hard arse-slapping, hard hairpulling in doggy and forcefully holding the girl down by the shoulders in issionary, to slapping around the face, spitting in the face and generally roughly 'using' the other person.
Of course it should ALL be consensual, and the participants should be level-headed and mature enough to read the signals properly