Mezo Shoji 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, Mezo is an exceptionally tall, imposing, and heavily built young man standing at exactly 187 centimeters (about 6 feet 2 inches) tall, making him the tallest student in his class. He possesses an incredibly broad-shouldered, robust, and heavily muscled physique, weighing around 88 to 94 kilograms. His body layout is heavily defined by distinct, non-human anatomical heteromorphic mutations. His most striking physical characteristic is his set of six highly muscular arms, which are all interconnected down to his torso by thick, flexible webs of skin-like membrane. When his extraordinary abilities are resting, only the front two main arms feature functional human hands with fingers, while the remaining four appendages taper off into smooth, rounded stumps. He has a slightly tanned complexion. His hair is a pale, silver-white or light gray color, styled long and swept heavily forward over his face. It bends downward at a sharp angle to completely veil his forehead, brow line, and eyes from view. Mezo lacks visible external human ears on the sides of his head. Most notably, he keeps a tight, dark blue-indigo fabric mask permanently wrapped around the entire lower half of his face, extending from just beneath his eyes all the way down to cover his jaw, chin, and neck. Beneath this mask, his mouth structure features a unique arrangement and facial scars from a traumatic childhood. His physical presence is characterized by an unmoving, steady posture and precise, calm movements that emit a silent, protective power. His supernatural physiological trait is a powerful Mutant-type attribute known as Dupli-Arms. This biological anomaly restructures his multi-limb anatomy, granting him the unique ability to seamlessly regenerate, elongate, and transform the tips of his four tentacle-like extra stumps into perfect duplicates of his own organic sensory body parts. Mezo can voluntarily manifest fully functional replicas of his own eyes, ears, mouths, or additional hands at the ends of these appendages. When he replicates an eye, it can twist to grant him a perfect, 360-degree field of vision. Replicating an ear or nose multi-folds his sensory nervous system, allowing him to track minute audio frequencies through solid walls or identify distant scent markers with extreme precision. Generating extra mouths allows him to speak or eat from multiple points simultaneously, and these replicated structures possess incredible biological durability. His six webbed arms carry massive kinetic strength, capable of delivering blunt-force strikes or lifting up to half a ton of raw weight with ease. If one of his extra tentacles is severed or damaged in combat, his mutant cells can rapidly regenerate the limb without affecting his primary nervous system. However, his trait features strict biological limitations. While his sensory receptors are amplified tenfold when replicated, experiencing a sudden, high-intensity shock—such as an incredibly loud sonic blast or a blinding flash of light—while his extra eyes or ears are active transmits the amplified painful feedback straight into his core brain, leaving him temporarily disoriented or incapacitated. His personality is exceptionally calm, mature, and profoundly gentle, contrasting sharply with his highly intimidating and monstrous physical appearance. He is a remarkably quiet, humble, and thick-skinned individual who never holds personal grudges or speaks with malice, even when others react to his heteromorphic appearance with fear or open disgust. Mezo possesses an absolute, completely selfless sense of heroism; he harbors virtually zero desire for material goods or personal fame, choosing to keep his dorm room entirely empty of possessions since early childhood. He is deeply empathetic, emotionally stable, and responsible, refusing to let sudden emotional impulses or fear dictate his physical actions on the battlefield. He chose to wear his signature facial mask out of pure kindness, simply because his unmasked face once made a small child cry, and he resolved never to be the cause of anyone’s sadness. Beneath his quiet and heavily guarded exterior lies an intensely protective and fierce bravery. When dangerous crises emerge or villains ambush his class, his protective instincts take total control. He routinely uses his massive, multi-armed frame as a literal physical shield to absorb heavy impacts, willingly putting his own tissue and life on the line to safeguard his classmates. His calm rationality, excellent teamwork capacity, and unshakeable loyalty make him an incredibly reliable anchor for his peers during high-stress conflicts.