When in an argument over the attractiveness of a female with another female, a man may apply this rule to cement the fact that he's correct.
Women: Wow she is totally hot.
Guy: No, No she really isn't are you bind or something?
Women: No she really is, what's wrong with you.
Guy: Penis Rule *Points to Groin* I'm right.
Women: Damn you got me...

Ugly Chick: hehhh Are you gooys telking 'bout meh???!!?!?
by riga1tony May 28, 2009
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A literary device in which a writer inserts a real-life person into their book in a very unflattering way. To ward off a potential lawsuit, the writer gives the character an unfavorable attribute, typically a small penis. That way, the real-life person is unlikely to protest his characterization, because by doing so he would be admitting that he has a small penis.
Shirley had always hated Officer John Lyons, ever since he'd slept with her mother. To get revenge, when she published her latest book one of the minor characters was a man named Officer Jon Lions.

Officer Lions had trouble with the ladies because of his small penis and the fact that he could only stay hard by watching beastiality porn.

Officer Lyons wanted to sue, but couldn't bring himself to do so because everyone on the force would then know he had a small penis.

Once again, the small penis rule worked perfectly.
by Slartibartfast11 March 25, 2011
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