What is Flu Shot?
1.
When you've had enough of someone. So you take a pen and preferably stab them in the eye or somewhere else on the body.
"Man this customer wont stop fuckin' complaining about this bread. Imma give em' a flu shot!"
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2.
Doing a shot of liquor (usually whiskey) out of a male's foreskin.
I was hard as a motherfucker after I did a Flu Shot out of that stripper's tasty foreskin.
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