Not just a cock, but the Head of all Cocks and some assholes.
When it's not enough just to call someone a dick head.
When someone gets you so pissed off at them you can not logically think of a insult that fits them, then they become a Grand Master Cock Dragon.
Soup:Dude why do you keep jankin my kills?
Blackop: cause I guess I am a cock. I really don't give a damn man!
Soup: (Pissed off to no resolve) Fuck you you fuckin cock ass... You Fuckin fuck... Your uh... Uhh.... I don't know a Fuckin Grand Master Cock Dragon bastard!!!
Blackop:...... Thanks buddy.
When a girl sucks a guys dick violently, vigorously and gags on every stroke, because she wants to fuck the guy but the guys not interested or is too hammered to fuck and just wants to sleep but the girl won't take no for an answer.