A bad case of penis typically occurs when the female in question essentially reveals her metaphorical penis. She does this by saying masculine phrases, such as "bro", "chill", "man", and "dude".

The phantom penis may also be revealed if the female swears excessively, and calls males "faggot" when she doesnt get her way.
Bro number 1: "Dude, would you have sex with Courtney?"

Bro number 2: "Hell no, shes got a bad case of penis!"

Courtney: "Shit, bros! I didn't know you were here! Let's chill."

Bro number 1: "I see your point..."
by Middlecitykid17 February 24, 2011
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