jackin flaps
A woman's way of getting off by rubbing her snatch flaps like a kid shoveling dirt. It's like a guy jacking his dong, but with more squish and less meat.
My cousin was jackin flaps in the bathroom while I was eating my lunch.
She was jackin flaps so hard, the toilet was shaking.
He texted me, 'Your sister is jackin flaps in the car, and I'm stuck next to her.'