Smack the Sack
To masturbate at such a high speed that your hand smacks your scrotum and makes a wet smacking noise.
Yea, I used to smack the sack, but then it got to loud and my parents heard.
She smacked on my nut sack
MAle genetalie that has been toyed around wiht a female lifeform.
OH man dude she done smacked on my nut sack.