What is Dickass Motherfucker?
1.
Due to the action of homosexual sex in a gay couple, of the thrusting of the "dick" in this case into the "ass" of another. Hence dickass motherfucker.
Motherfucker is used only as an insult endstop, to bring finality to the statement or insult.
"...You southern fried dickass motherfucker....!"
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