1. a small tuft of hair surrounding the anus that resembles a skirt 2. Incomplete Brasilian bikini wax
"I was going down on this chick last night and looked down from her cooch only to find an ass skirt below. She needs to spend mo' money on her wax job."
When the girl your sleeping with takes your shirt and puts it under her ass while your fucking in hopes of no leaving evidence on her relatives, boyfriend, or sisters bed.