slappin' sacks 

When you are double penetrating a girl doggie style, you are slappin' sacks with the other gentleman involved.

Howard and I were slappin' sacks the other night and that bitch pulled out shot his wad on my nuts.

slappin' sacks by whitey63 November 27, 2006

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