An old, hairy vagina marked by well worn usage and sporadic bald spotting of the pubic hair.
Little Donny happen to spot his naked grandmother coming out of the shower. Her mangy muff startled him and scarred him for several months. Every time he went to wank one out it was all he could envision.
Mangy means having mange or being diseased but there is a girl who has this disease who has a secret Instagram account named after the infamous mangy with an added nose. She posts funny things and her friends and of course of her fish flops too ;) She is not afraid to post anything so don't let her catch a bad photo of you or it will end up on mangy for sure.
Heidi: Um wow, what's that Instagram account?
Ady: Uh...duh that's mangy nose!