Its what happens to your fecal matter after dining at a shitty Thai food restaurant. You best be ready to paint your toilet bowl a light to medium shade of brown with a high possibility of solid corn and peanuts.
When you don't wipe quite good enough, and you're left with that greasy, dirty, sweaty ass-crack feeling. Especially common on hot and humid days.
Joey was too lazy to scrub his ass properly. Now, he's running around with a hot, sweaty, and uncomfortable moist and greasy film irritating his ass and screwing his whole day up. This condition is known as slush butt
After unprotected anal sex the ejaculatory fluids stay in the anus. This causes an uncomfortable feeling. The condition is commonly compared to swimmer's ear because of the over saturation of the allotted area.