A bald, unassuming man in his mid-20s wearing a plain yellow jumpsuit, red gloves, boots, and a white cape. His face is round and simple, almost cartoonishly blank, with dot eyes that only show real intensity in a fight. Despite being the strongest being alive, he carries himself with total apathy — slouched posture, deadpan expression, and a chronic look of boredom. His defining trait is his crushing existential problem: no opponent has ever taken more than one punch, leaving him unable to feel the thrill of battle anymore. Off-duty, he's a frugal bargain-hunter obsessed with sales and coupons, living in a cramped apartment in City Z.

A tall, athletic-looking young man who is almost entirely cyborg beneath a human face — his real body was destroyed years ago. His mechanical frame is sleek and metallic, with visible joints, vents that release steam when he powers up, and glowing eyes that shift color with his emotional state. He typically wears a simple, practical outfit that shows off his engineered limbs, built for combat with retractable weapons like incinerators and rocket-propelled fists. Serious, intense, and driven by a singular purpose — revenge against the cyborg who destroyed his life — he treats Saitama with unwavering, almost reverent loyalty as his self-declared disciple.

A striking young woman with long, dark purple/black hair and sharp, confident eyes, often dressed in fitted, stylish outfits with a witch-like flair (pointed elements, dark colors) that hint at her esper powers. She carries herself with icy composure and controlled pride, projecting authority as the leader of her own hero group, the "Blizzard Group." Beneath the aloof exterior is deep insecurity, largely rooted in living in the shadow of her older sister. Her psychic abilities let her manipulate objects at range, and she values control — over her powers, her subordinates, and her reputation — above almost everything else (she is Tatsumaki's young sister).

Small in stature with a childlike appearance, but topped with a wild mane of vivid green hair that often floats or swirls when her psychic powers activate. She dresses in a simple, dark, form-fitting outfit suited for combat. Her demeanor is the opposite of her size — short-tempered, arrogant, and quick to mock anyone she deems weak, backed up by devastating telekinetic power that lets her casually crush buildings or hurl enemies through the sky. Despite the abrasive attitude, she has a softer, protective side that surfaces around her younger sister, Fubuki, and the few people who manage to earn her respect.

An elderly martial artist with a lean, wiry build that belies enormous physical power — his muscles are still sharply defined despite his age. He has a long white beard and hair, often tied back, and dresses in traditional martial arts attire, typically a simple gi in muted tones that reflects his humble, disciplined nature. His face is weathered and stern but carries a calm, grandfatherly warmth. As the founder of Water Stream Rock Smashing Fist, he embodies patience and restraint, preferring to mentor and de-escalate rather than fight, though his strikes carry city-block-leveling force when unleashed. He's soft-spoken, deeply principled, and one of the few heroes who treats Saitama with genuine respect and curiosity rather than jealousy.

A tall, heavyset man with a perpetually grim, hardened expression — dark hair, a serious brow, and a face that looks like it belongs to a seasoned, battle-worn warrior. He dresses plainly, nothing flashy, which suits his reputation as the "strongest man on Earth," a title he never actually earned through combat. In reality, he has zero fighting ability; his terrifying reputation comes entirely from being present at the aftermath of Saitama's real victories. His defining trait is crippling anxiety and cowardice hidden behind a stoic, intimidating poker face — he's a master of bluffing stillness and silence to avoid ever being tested, all while riddled with guilt over the fraudulent legend built around him.