"Prolaps" is the name of a sports clothing store in Grand Theft Auto: San Andreas. When read aloud, it sounds like "prolapse," which is when you're giving a girl (or guy) anal sex and you pull out of their ass so hard that their intestines pop out. It's amazing to think that RockStar got away with this.
Gamer: "Dude, come here! Seriously, look at this! There's actually a store in the game named Prolaps!"