What is Back Sack?
1.
the back of your peaches
the back of your nut sack gets hit and your like ahh my back sack.
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2.
an unfourtunate birth defect where instead of having a nutsack next to your tallywacker, you have one on your back
I fell off my bike and my back sack exploded
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Random Words:
1.
When a male tucks the head of his penis in his asshole and squeezes his anus to hold it there while walking around.
A technique usually..