it is when a guy puts peanut butter on his penis and shuves it up a womens ass and jizzes witch leaks out to create ass nut butter
example "dude that girl wanted me to ass nut butter her"
"really did you shuve it in her ass"
"hell yah" :P
"really did you shuve it in her ass"
"hell yah" :P
by mr.smarterass April 03, 2009
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