Girlfriendoppotamus
A girlfriend whose girth is equal to that of a hippo, but has the ability to mask said girth to her boyfriend even though it is evident to the rest of the world.
Jordan: "what do you think of my new chick guys?"
Mike: "Where is she behind the fat chick?"
Jordan: "what do you mean?"
Mike: "dude, you have a Girlfriendoppotamus"
Mike: "Where is she behind the fat chick?"
Jordan: "what do you mean?"
Mike: "dude, you have a Girlfriendoppotamus"