The noise that results from the slapping of a sweaty scrotum against one's ass during butsex. Also, someone who is known to take multiple cocks in the ass in one day on a regular basis.
1)The faggots next door made a belfo that woke up the whole neighbor hood. What a bunch of assholes.
2)That guy is such a fucking belfo his asshole could hold the Titanic and a black cock.
by King-Shit November 27, 2008
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