make a shake with whatever's in the frig and give it to the unsuspecting customer. just get whatever is in the frig, mustard, ketchup, syrup, jelly, mayo..etc...It's the most disgusting thing you will ever drink and will want to throw up right after. You have to make it look like a convincing shake, so put like ice cream milk and whipped cream and a cherry on top.
you could also put dip (chewing tobacco) in it to give it a nice spice.
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