sack slapping 

when you having sex and your balls are slapping against the girls ass or leg

i was fucking this girl from behind and i was sack slapping her ass

sack slapping by sack slapping July 18, 2014

slapping the sack 

When someone with a tiny penis "try's" to masturbate. Their peter is so tiny that they end up just slapping their sack

Jessica: I caught Perry beating off in the bathroom yesterday.
Amanda: Trust me, his dick is so small he was just slapping the sack.

slapping the sack by Jameshasahugecock May 13, 2018