Having dump crotch is when your crotch area literally smells like a sweaty dump. This is achieved by intense body sweating in and of the area typically caused by exercise. Dump crotch is not to be confused with poor hygiene or other scent related issues with the crotch region.
My god I sweat so hard during that Beachbody 80 Day Obsession workout; oh, DAMN I stink, I got dump crotch!
A King Dunlap is when you have an extremely large amount of foreskin, so much so that you cannot see the actual penis.
"My King Dunlap is so big I have to pull it back to pee."