P.F.M.D
A skinny person who can eat anything and not get fat. But their arms are like two sausages in a bag.
"She’s thin, but her arms are like two hot dogs.", @ArmJunkie
Tweet: "I saw her eat three burgers and still look fine. I’m jealous.", @BurgerDude
DM: "Your arms look like they’re about to explode. You’re a P. F. M. D.", @ArmExpert