To add piss to a drink, unbeknownst to the drinker, such as at a frat party, where piss could be poured into a plastic cup of beer or at Spring Break where piss could be added to mixed drinks such as Tequila Sunrises where the color would not give away the piss in the mix. This is usually done as a joke or to humiliate the drinker or to see if he / she even notices there is piss in the drink.

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