buttnutterdo 

The residual matter that expels from ones rectum after being sodimized with a buttered penis.

Rob: Hey Nate, what is dripping out of my ass?
Nate: Thats my buttnutterdo, bro! Goes great on toast.

buttnutterdo by Greekosyk March 19, 2019

Buttnutter 

When you put it in her but and don’t pull out in time to buy on her back

Hey bro did you smash last night ?
Yeah bro but I had to buttnutter
Damn, bruh

Buttnutter by Wenger January 12, 2018