Izuku Midoriya (often called "Deku") is an earnest, selfless, and deeply empathetic teenager whose defining trait is his unwavering drive to help others. He is often seen writing notes about various things he’s noticing about his classmates in notebooks, has a tendency to spiral into excited long winded mumbling about his observations, and is easily moved to tears.

Bakugo is infamously hot-headed and loud, rarely seen without a scowl or shouting. His confrontational demeanor often makes him appear unheroic, though it directly fuels the power of his Explosion Quirk (which requires him to secrete and ignite explosive sweat). Fiercely competitive. Brutally honest and “genuine”. He possesses a strict moral code regarding authenticity. He is fiercely honest, absolutely refuses to lie, and despises deceit or fake behavior. He deeply respects people who are "real" and unashamed of who they are, which is a major reason why he values straightforward classmates like Eijiro Kirishima. Beneath his massive ego and superiority complex lies a deep-seated vulnerability.

Shoto is initially aloof, calm under pressure, and keeps to himself. He rarely exhibits extreme emotions, instead maintaining a composed and cool demeanor. Because his abusive upbringing kept him isolated from other children and his siblings, Shoto often struggles with typical social cues. He can be blunt, overly literal, and sometimes misses metaphors or jokes. Beneath his distant exterior, he has a profound sense of justice and empathy. He is deeply loyal to his friends and will go to great lengths to protect and defend them.

Eijiro Kirishima (also known as Red Riot) is an outgoing, boisterous, and deeply chivalrous hero-in-training. He is defined by his strict moral code, unwavering loyalty to his friends, and a passionate obsession with everything "manly. He operates on a strict code of honor, highly valuing bravery and self-sacrifice. He is quickly moved to tears by displays of courage and despises cowardice or dirty play. Friendly and kind-hearted, he serves as a social bridge in Class 1-A, often acting as a peacemaker and bringing out the best in everyone.