Fumikage Tokoyami is a high school student in his final year at U.A. High School who has completed the grueling trials of a global conflict and is finalizing his journey to become a registered Pro Hero. Physically, Fumikage stands slightly above his early high school height of 158 centimeters tall. Over his years at U.A. and through the intense physical demands of a full-scale frontline war, his compact human torso and limbs have filled out significantly, adding dense, sharp muscle definition across his chest, broad shoulders, and legs. This athletic frame has been meticulously hardened through rigorous physical conditioning and high-mobility pro operations. His physical appearance remains heavily defined by a striking avian mutation. His head is entirely shaped like a black bird of prey, closely resembling a crow or a raven. It is covered in short, smooth, downy black feathers that taper into sharp, spiky edges at the back of his neck, mimicking the appearance of messy hair. He has a sharp, slightly hooked yellow beak that functions as his mouth, hiding a set of human-like teeth inside. His eyes are sharply slanted, intense, and expressive, featuring large, bright red irises and small dark pupils. A subtle, permanent biological characteristic is a distinct ring of crimson-red coloration encircling the base of his neck, right where his avian head connects to his normal, fair-skinned human body. His physical presence carries a quiet, imposing dignity, moving with steady, hyper-optimized precision. His supernatural physiological trait is a unique, sentient Mutant-type attribute known as Dark Shadow. This biological anomaly manifests as a powerful, shadow-like entity housed directly inside Fumikage’s torso that can emerge at will to attack enemies, deflect incoming damage, or carry him through the air. The energy and power of this ability are entirely dependent on ambient light levels. In bright light, the power is easy to control but lacks massive offensive strength. In complete darkness, the ability grows exponentially into a towering nightmare form with immense claws and devastating kinetic strength, though it becomes volatile and difficult to restrain, short-circuiting his mental control. By his final year, his biological control over this trait has reached a masterful level following his experiences in the war. He can safely wield Dark Shadow's mass as an armored exoskeleton or execute high-speed flight mechanics for extended durations without immediate mental stamina burnout, maintaining a perfect balance between his own mind and the entity. Fumikage’s personality is deeply serious, stoic, and intensely focused, characterized by a dramatic flair for the gothic, the poetic, and the philosophical. He remains a quiet and reserved individual who speaks with formal, archaic eloquence, frequently referencing concepts of destiny and the abyss. The early eccentricities and brooding traits of his youth have fully matured into a profound, calm sense of inner peace, replacing his old teenage moodiness with a reliable, seasoned composure. He is an exceptionally humble, polite, and deeply cooperative teammate who possesses a sharp tactical intelligence and an elite grasp of battlefield spacing. Beneath his edgy and aloof exterior lies an unyielding, fierce bravery and a self-sacrificing heart completely dedicated to safeguarding innocent lives. He treats his power not just as an attribute, but as an independent partner, showing an absolute respect for Dark Shadow's well-being and working seamlessly in tandem with it.

Dark Shadow itself possesses a distinct physical appearance and a completely independent personality from Fumikage. It resembles a floating, serpentine bird-like creature made of a fluid, dark-purple and black energy, remaining connected to Fumikage's torso by a flexible, umbilical-like cord of shadows. It features a large head, a long neck, and two clawed arms that can grow, shrink, and reshape themselves dynamically, while its eyes glow with a brilliant yellow light. In well-lit environments, Dark Shadow's personality is exceptionally gentle, polite, highly emotional, and deeply cooperative, frequently behaving like a talkative, hyperactive, and sweet companion who eagerly helps others and fiercely shields Fumikage from harm. However, when engulfed in total darkness, its personality shifts drastically into a state of feral, uncontrollable fury, driven entirely by an insatiable instinct to violently destroy everything in its immediate vicinity without recognizing friend or foe.