A troll Fetus is an absolute abomination of a creation. It can be a person, place, or thing
It looks like (and smells like) if all of Cleveland Ohio was combined into a single object and smelled like old man piss. Kind of like the whole Browns franchise come to think of it.
Guy 1: Bro that girl looked like a troll fetus!
Guy 2: Gah damn what is that foul abomination that is lumbering down the street!