When two Lactose intolerant men both eat an entire tub of ice cream then proceed taking turns riding each other's cocks until the rider sprays the ridee's crotch with a stream of diarrhea.
The winner is determined by how kinky the couple is. The loser buys the anti-diarrhea meds.
Sorry I'm late to work today, Bill and I played Dick Riding Roulette last night and my stomach has been upset all morning.