1. Someone who just doesn't let up. He/She keeps going and going and just doesn't get the message to shut up, cause the "joke" isn't funny anymore.
2. Someone who has no "off switch" or can't tell a story without taking 3 days to tell, when in the end it goes nowhere.
Jason: (tells an endless story that goes nowhere)
Jeff/Glenn: You're a f*&%ing JERK, Jason, shut up, you make no sense.
Jason: (then proceeds to bash mothers and spouses)
Glenn: Shoot this JERK!!!