A person who claims they want to stop smoking and drink less and then calls you up at 22:30 on a Monday/Tuesday/Wednesday night after you have already gone to bed to go to the local pub where the losers hang out. Can, under certain circumstances, also be referred to as "Douche-a-bag". Displays primate-like and obsessive compulsive behaviour and will run away when frightened.
Person a) "Let's go out and get trashed!"
Person b)"Oh snap, don't pull a Grietjie on me!"