When someone is in a particularly foul mood first thing in the morning. Many people will have a cup of coffee before anything else is taken care of. Therefore their coffee must have been pissed in to start their day off so badly.
Joe: "Hi Jack! Wonderful day isn't it?"
Jack: "Ah fuck yourself you fucking fuck!"
Joe: "Well who pissed in your coffee this morning asshole!"
by Jumpingrat March 25, 2007
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