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1.
When a male shits into a female's neck and it falls down her cleavage resembling a waterfall.
Person 1: YO I GAVE THIS NASTY BITCH A HUGE NIAGARA SHITS LAST NIGHT!!

Person 2: oh shit you lucky basterd

Person 1: THE BEST PART WAS I TOOK ABOUT 8 LAXATIVES THAT AFTERNOON
by THE ASS FUCKER July 24, 2010