Sandpaper Swing 

The humping of Dry Vagina.
Usually associated with Grandma's.
Can also be know as rubbing fronts.

Me: Dude that was my grandma.

Buddy: Yeah I know. I did her.

Me: That's disgusting.

Buddy: You're telling me she was a Sandpaper swing.

Sandpaper Swing by gilfiemcgilfgilf September 24, 2007