1.flossing one's ass.
2.To floss an ass.
"Robin likes to Flass his mom"
"Where is Sanders? He's flassing"
"Sure am Glad I'm not flassing....like Robin is in the Gazebo...with his mom"
1. To floss inbetween buttcheeks with a variety of different things.
2. A form of torture (see 1.)
3. A sexual position (see 1.)
Robin enjoys flassing his mother with a gazebo.
We'll make them talk by flassing them into confession.
Don't stop flassing me!