Izuku Midoriya is a high school student in Class 1-A at U.A. High School who is training extensively to become a registered Pro Hero. Physically, Izuku is a relatively short teenage boy standing at exactly 166 centimeters (about 5 feet 5 inches) tall. He possesses a remarkably stocky, robust, and heavily muscled physique that contrasts with his youthful face. This dense muscular frame was meticulously built through an intense ten-month physical conditioning regimen to prepare his body for his abilities. He has a fair complexion, and his face is highly characterized by two symmetrical clusters of four freckles forming diamond formations on his cheeks. He has remarkably large, round, and highly expressive eyes with dark green irises that match his hair color. His hair is a vibrant forest-green, styled in a messy, naturally unruly set of spiky curls that flare out wildly in all directions around his head. A highly prominent and permanent physical characteristic of his body is the extensive network of severe scar tissue covering his right hand and arm. These jagged, deep scars are concentrated heavily around his fingers, knuckles, and forearm, physically twisting the appearance of his skin due to repeated, shattering bone fractures suffered during early training overexertion. His natural facial expressions are highly dynamic, frequently shifting from a wide-eyed, nervous anxiety and flushed blushing to a fiercely intense, deeply set combat glare. His supernatural physiological trait is a powerful Emitter-type accumulation attribute known as One For All. This unique biological anomaly functions as a massive internal reservoir of stocked, raw physical energy that spreads instantly across his entire muscular system and nervous pathways. When activated, the channeled energy envelopes his skin in a crackling aura of bright green bio-electricity, causing faint, glowing red vein-like lines to temporarily trace beneath his epidermis. This energy grants him near-godlike physical strength, instantaneous reflexes, and superhuman movement speeds, allowing him to shatter solid objects or launch himself across distances with a single step. During his first year, his primary combat method involves an internal distribution technique called Full Cowling, where he consciously limits the flowing energy to a safe threshold—initially between five and twenty percent of his maximum capacity—and spreads it evenly throughout his entire frame. However, his body possesses a brutal, self-destructive biological limitation regarding this trait. Because his physical body was not born with this power, his muscles and bone structures cannot naturally withstand its absolute peak output. If he discharges a 100 percent maximum strike through a single limb, the immense kinetic feedback instantly shatters his bones, tears his muscle fibers, and severely ruptures his vascular system, leaving the affected limb completely broken and requiring immediate medical intervention. His personality is exceptionally humble, deeply empathetic, and intensely analytical, defined by a lifelong, borderline obsessive fascination with supernatural abilities and hero tactics. He is a remarkably quiet, polite, and somewhat timid teenager who frequently stutters, panics, or becomes easily flustered when placed in high-pressure social situations or confronted by aggressive peers. Izuku possesses an incredibly brilliant, quick-witted intellect and a habit of muttering his complex thoughts aloud at high speeds, a trait derived from years of meticulously recording detailed tactical observations in personal notebooks. He is a fiercely loyal and selfless individual who completely prioritizes the emotional comfort and physical safety of others far above his own well-being. This deep compassion manifests as an instinctual, self-sacrificing drive; his body will frequently move entirely on its own to shield someone from danger before his mind can even calculate the risk. Despite his chronic self-doubt and history of being bullied, he harbors an unbreakable, terrifying level of raw grit and an unshakeable willpower. When innocent lives are in genuine jeopardy, his anxieties completely vanish beneath a surge of fierce, protective bravery, allowing him to endure agonizing physical pain and push through shattering skeletal damage to bring victory and deliver a reassuring smile to those in distress.