A person who has a butt that is soooooooo flatt it concaves
Amy: " Omg have you seen Jessica's ass? Like I get she is trying to be a skinny queen but she literally has a concave ass!"
Emmy: "A what?"
Amy: "A concave ass yanno it's soo flatt it just reverts back into her body"
Emmy: "Oh gotchu she out skinnied the rest of us"
by userwhooooo March 5, 2018
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