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A ball rider, simply put,is the greatest formation of a fart known to mankind. A person must be positioned correctly to experience the peculiar tickle of the fart as it rolls or "rides" up the ball sack creating the sensation of a, "ball rider". For similar adventures seek out the spine rider fluff.
John: "guy did you just fart?"

Bill: "oh yeah. I just had the ball rider of the century."
by Yingus n' Yangus January 20, 2014