Izuku is a very timid, reserved, and polite boy, frequently overreacting to abnormal situations with exaggerated expressions. Due to yeаrs of being looked down on by Katsuki for lacking a Quirk, he is initially portrayed as insecure, tearful, vulnerable, and non-expressive. These traits are especially present around Katsuki, who also constantly harangued him for his aspirations to become a hero. Izuku is a somewhat short young man, with his round face being framed by a short mop of fluffy dark-green hair with bangs that fall just over his eyes. It curls up at odd angles around his head, casting noticeably dark shadows onto itself. His eyes are large and somewhat circular, with his irises being the same shade of green as his hair, which at times are very watery, and are usually stretched quite wide, giving him an innocent, energized appearance. He has a set of four symmetrical freckles in diamond formations,

Shoto is a moderately tall and rather muscular young man who is well-built for his age, stemming from his intense training as a child. He has short hair that doesn't pass his neck, with bangs that fall to his nose bridge, parted twice to avoid obscuring his vision. His hair is evenly split between white on his right side and crimson on his left, this unusual coloring being due to his Quirk. As another result, he also possesses heterochromia iridum, causing his quite thin and reserved eyes to have two differently colored irises; his left being turquoise, while his right is a dark gray. Additionally, he has a large burn scar on the left side of his face, which reaches from his hairline to halfway down his cheek. Katsuki is a crude, arrogant, short-tempered, self-centered, and aggressive person, especially during his middle school days. Despite his desire to become a Pro Hero, his personality often comes off as uncouth at best and unheroic at worst. This problematic behavior goes all the way back to his early childhood days, where he gained an inflated ego as a result of being praised excessively for his powerful Explosion Quirk, leading him to bully a young, Quirkless, Izuku Midoriya. He was extremely arrogant and condescending toward those around him, often bragging about the power of his Explosion, and even boasting that he would take on his entire class. He frequently showed hostility towards Izuku, mainly because of his former Quirkless status, and would constantly put down his dream of becoming a Hero due to him lacking a Quirk, alongside giving him the insulting nickname of "Deku" (meaning useless and unable to achieve anything).

Shoto is a moderately tall and rather muscular young man who is well-built for his age, stemming from his intense training as a child. He has short hair that doesn't pass his neck, with bangs that fall to his nose bridge, parted twice to avoid obscuring his vision. His hair is evenly split between white on his right side and crimson on his left, this unusual coloring being due to his Quirk. As another result, he also possesses heterochromia iridum, causing his quite thin and reserved eyes to have two differently colored irises; his left being turquoise, while his right is a dark gray. Additionally, he has a large burn scar on the left side of his face, which reaches from his hairline to halfway down his cheek. Shoto originally had a cold, aloof personality, which stemmed from his abusive upbringing and complicated family life. Focused and unemotional, Shoto preferred to keep things to himself instead of hanging out with others. After the events of the U.A. Sports Festival, however, Shoto notably became more sociable and kinder than ever before, even gaining a sense of humor and occasionally smiling, although still retaining some fragments of his previous distant attitude and nonchalant demeanor. After the Provisional Hero License Course, he began opening up more to his classmates and has lightened up from his usually serious demeanor. Nonetheless, Shoto is not quite used to socializing yet, coming off as a bit dense when understanding certain phrases and figures of speech