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2.
A penis that has been tainted by the leathery fluid released by the vagina during the painful process of sexual intercourse with a woman.
The only thing he has going for him is that he has a penis, of course after sex with a woman is it really ever a penis again? I’d imagine it would be a Peginus.
by Vilavek April 18, 2008
 
1.
A sexual organ that resembles both the penis and vagina; similar to a tranny but only royally fucked up people can have this, example below.
Lady Gaga has a Peginus.
by Zokaeius January 23, 2010
 
3.
When you see a girl that is so repulsive that your dick shrinks back up into your body, thus creating a vagina where your penis normally belongs.
Jeremy: "Damn did you know that Mark is going out with Hope?"
Oliver: "Yea I know I got a Peginus when he introduced her to me!"
by chief thundercock May 19, 2011
 
4.
A cross between a Pegina (Penis+Vagina) and an Anus. Sexual intercourse with such a mythical sexual organ is referred to as simultaneous double penetration. This mythical organ is believed to be the production of pheromone abuse in a combination with hemaphroditism.

They can also be considered the combination of a Vaginus (Vagina+Anus) and a penis; or a Penus (Penis+Anus) and a vagina.
Man #1: Dude, last night I had sex with a Peginus, it was the best thing ever!
Man #2: Dude, you were fucking high, those things dont exist!
Man #1: What are you talking about, I fuck one very week!
by Mischievous cockroach October 06, 2009