The act of wanking where the object of fantasy is often the focus of some kind of anger, but also incredibly attractive. The wanking is made that much more pleasurable when it demeans the super hot person in your mind.
I hate my teacher with the unbridled fury of a thousand suns...but she's also fucking hot, so I'm gonna do some angerbation.
Guy 1: That bitch in the gym pissed me off.
Guy 2: Should make for some great angerbation then.