When you're having anal sex with a female (or male) and you pull out before you cum.
Back away, and try to ejaculate into the asshole of your partner from a distance. This is the "poop hoop". Points vary depending on the distance in which you came. You can only score if you actually land your semen within your partner's asshole.
John: "Dude, I just scored a 3 pointer poop hoop on Susan last night!"
Jack: "Wicked sick man, the highest I ever got to was 2 points."