Used in conjunction with Motherfucker. A term for a nut who wanks. Frequently. Often used as derogatory. However, in extreme circumstances can be a compliment.
eg 1 Dude 1: Looks like you're wasted.
Dude 2: Wank-nut. Motherfucker
eg 2 Dude 1: You're a wank-nut.
Dude 2: You ass-goblin. DIEE !!!
eg 3 Dude 1: You're a wank-nut.
Dude 2: YAAAYY ! Thanks, Cletus!You're such an ass-hat!
Dude 1: Gee, thanks !! Lets be friends!!