Leaving someone behind (likely an annoying person) like you would leave a fat chick chatting you up at a bar, usually without said fat chick's knowledge.
Bro Dude: Hey, I thought you were coming with Larry?
Bro Ham: He was taking so long, I fat bitch'd him!
found in the upper cetre of the back between the shoulder blades where a womans bra strap would be. people with alot of weight/skin/fat have this more noticably.
all you have to do is place your thumb at the base of the neck, fingers about 3 inches down and pinch to find it.