Taishiro Toyomitsu

In his fat form, Taishiro is a large, round man, easily towering over other adults. In this form, his mouth is wide, and his nose is smaller, which gives him an odd look alongside his odd body proportions. After burning through his fat, however, it is revealed that he is pretty muscular, and his body adapts to conventional proportions.

His hero costume consists of black pants and an orange, zippered hood, which has the initials of his alias on the front of Fat Gum, written with a clear F, G and an inverted F. Alongside them, he also wears gloves, metallic boots, and a mask that goes around his eyes and over his forehead.

His hero costume in My Hero Academia: Vigilantes, which takes place several years ago, is the same, except that the initials of his alias are written with only a black F and G. In addition, he wears dark forearm guards. Taishiro appears to be constantly hungry, which leads him to eat a lot. He is very friendly towards civilians and other heroes, appearing to be a playful and carefree person. However, he gets earnest when the situation demands it, always having the work ethic of a hero.

Whenever Taishiro is focused on doing the right thing, he becomes impulsive and determined, especially when life is at stake. In this case, he becomes utterly enraged, impatient, and disapproves of lengthy operations.

Due to his time working with the police, Taishiro is very knowledgeable about Japan's underworld. He can recognize potential when he sees it, complimenting Tamaki's prowess as a hero, though the latter thinks of it as harassment. Taishiro also extends this to Eijiro after he held his own against a villain and praised his will to continue.

Taishiro is kind and will prioritize helping people and saving lives first. He cares deeply about the well-being of others, especially those in his care, which is why he becomes so angry when villains threaten the lives of others. After the fight with Eight Bullets, he was perturbed about Eijiro's state and cried tears of relief when he realized Eijiro was fine.