Self explanatory. If you don't get it, let me explain for yourself. "Buttering the bean", or "buttering your bean", is in essence busting your nut full of semen on a girls clitoral region, aka the "bean".
"I'm gonna butter your bean you dirty whore"

Guy 1 - "Oh brah, did you butter her bean last night?"
Guy 2 - "Yeah dude I hope I didnt get her preggers"

Girl - "MMMMMMM he buttered my bean so good last night, it took us hours to clean it all up!"
by Karl Hungus1 December 19, 2010
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