A secret term used in emergency rooms across the country to describe a jack-ass that pounds too many energy drinks and then thinks he's having a heart attack.
Scott pounded 8 rockstars today and wonders why he has chest pains; that dumb fucker gave himself a badcase of mangina!
The practice of neatly tucking your penis (and if you can , your testicles) back between your legs obscuring them from view to either achieve a comical or deeply perverse effect depending on your motive.
Comical:
"Wehaaay! Look at this lads! Check out my Mangina! I'm your Mum!"
Perverse:
"I'm trying to groom my girlfriend into being a lesbian. Tonight I will give myself a Mangina and see if she will go down on me."