He is an extremely fat individual. He appears to be an overweight young boy with medium-length blond hair parted in the middle piloting a six-legged mech suit. However, his apparent mech is actually several layers of hardened fat, and just an extension of his body. He is notable as he is one of the two individuals to have ever bought the game for the price, leading him to success great enough to found his own city and even enter Smash Bros.
It is heavily theorized by Pasquel FeelinSour that Fat Man will be included as one of the DLC fighters in the 2018 fighting game Super Smash Bros. Ultimate. This is unlikely, as the size of his enormous penis is far too massive to ever be rendered into the game. His testicles rival those of Jahseh's beloved pet, a pig with massive shit-covered balls. This theory is known as the Porkpill theory.