Sack Shift 

If you look closely at your testicular pouch for just a few minutes you will notice subtle movement of the skin your not in control of. Must be done sitting or laying down.

Employee: Sir, you have to leave the movie theater
Me: Shut up! I'm trying to watch my sack shift

Sack Shift by Mr. Theado June 19, 2016

sack or shaft 

hugely entertaining game played in drinking establishments. competitors take it in turns to display a small area of their genitalia through their trouser flies. the watching crowd then have to make their choice as to whether it is penis or testicle that has been exposed.

Boredom began to creep in, so a game of sack or shaft was initiated and quickly cheered everybody up.

sack or shaft by brown nose May 16, 2006

Shaft My Sack 

according to world english dictionary shaft is a slang term meaning "to have sexual intercourse with" and Sack as in a Ballsack a.k.a Your Testicles inside your Scrotum, so Shaft My Sack Means "To Be Intimate/Sexual With Ones Testicles"

Your Doing Real Good In COD So At The Lobby You Say to Them Shaft My Sack

Shaft My Sack by HB Security March 12, 2011