V. When a dude relunctantly has intercourse with someone whom he considers to be slightly repulsive, doing so solely out of obligation to his penis. This term is especially important when your bros ask you the age-old question, "Would you hit that?" in reference to a somewhat unattractive chick.
Biscuit Joe: "Hey, man, would you bang Caitlin?"
Grey Jiff: "Uh... I wouldn't enjoy sexing up Caitlin, but I feel like I owe it to my dick to get some action. I might not nail anyone else for a long time. So, yeah, I'd close my eyes, take a deep breath, imagine Jessica Alba, and obligation bang Caitlin's nasty ass.