Kazari Uiharu is a Level 1 esper enrolled as a first-year student in class 1-D at Sakugawa Middle School and serves in Judgment, Academy City's student-run law enforcement body. Her esper ability, "Thermal Hand," maintains the temperature of objects she touches. She possesses short black hair, brown eyes, and consistently wears an artificial hibiscus flower headband. Standing 152–153 cm tall, she is most often seen in her school uniform paired with loafers and loose socks. Typically polite, reserved, and humble, Uiharu consistently uses formal Japanese and honorifics. She actively imposes a "limit" on her behavior to maintain composure; without this restraint, she exhibits high energy and occasional airheadedness. She harbors a fascination with elite lifestyles, particularly the "Ojou-sama" culture of Tokiwadai Middle School, and enjoys sweets, though Judgment duties frequently interrupt her indulgence. Demonstrating a strong sense of justice and loyalty, she has shielded a child from an explosion and protected Haruue Erii from a falling lamppost. She shows no fear toward exotic animals, like Kongou Mitsuko's python. Her core role in Judgment relies on exceptional technical proficiency. Operating under the alias "Goalkeeper," she specializes in cybersecurity, hacking, and information gathering. She designed one of Academy City's top ten security systems, paradoxically surpassing the defenses of the city's central databases. This expertise proved critical during the Level Upper incident, where she distributed the removal program, and the Poltergeist arc, supporting investigations into Haruue Erii. Her abilities extend beyond computers; she memorized a giant mecha piloting manual overnight and effectively applied it during combat alongside Ruiko Saten. Uiharu joined Judgment in elementary school following a bank robbery where she was taken hostage and her senior, Konori Mii, was injured. Shirai Kuroko intervened, defeating the criminals with covert assistance from Misaka Mikoto. Inspired, Uiharu and Kuroko partnered in Judgment, vowing to uphold justice together. Their partnership involves Uiharu providing tactical and informational support from the office while Kuroko handles field operations. Early tensions stemmed from Uiharu's perceived lack of combat readiness, but their bond solidified through shared convictions, like apprehending criminals without waiting for Anti-Skill. Key developmental moments include comforting Ruiko Saten during the Level Upper incident after Saten despaired over her Level 0 status; Uiharu insisted personal worth transcends esper levels, emphasizing their friendship. During the Battle Royale arc, she protected Last Order from Kakine Teitoku, enduring torture and a dislocated shoulder while defiantly refusing to reveal the child's location until Accelerator intervened. Her courage also surfaced in the Poltergeist arc, personally supporting the suspected Haruue Erii. She demonstrated resilience again during the Academy City Invasion, distracting Kuroko to aid Mikoto. Her background includes a former vulnerability to illnesses, leading her to wear a surgical mask in early manga appearances. Her friendship with Saten involves frequent teasing, such as skirt-flipping, and shared café outings. She participated in broader events like the Daihasei Festival, pushing Kuroko's wheelchair during recovery. In spin-offs like *A Certain Scientific Accelerator*, direct appearances are limited, but her established connections to Last Order and Academy City's security systems imply indirect relevance to storylines involving the Misaka Network. Her Judgment role and technical expertise remain consistent across media, including games like *A Certain Magical and Scientific Ensemble*.