Nagisa Misumi attends Verone Academy as a middle school student, starting as a 14-year-old second-year and advancing to her third year. She excels as the lacrosse team's star player but struggles academically. Her everyday look includes short ginger hair, light brown eyes, and slightly tanned skin, typically dressed in a pink jacket over a white-and-black raglan shirt, red skirt, pink socks, and sneakers. For lacrosse, she pins part of her hair with a pink heart-shaped clip and wears a numbered sports uniform. Her transformation into Cure Black begins when Mepple, a fairy from the Garden of Light, arrives during a meteor shower. After meeting Honoka Yukishiro (Cure White) and Mipple at an amusement park, they face a Dotsuku Zone attack, triggering their Pretty Cure transformation. Nagisa initially resists this destiny but gradually accepts it, forging a deep alliance with Honoka. As Cure Black, she gains elongated hair swept aside, silver heart-shaped earrings, and a black combat outfit featuring pink ruffles, a heart-tipped belt, and magenta boots with leg warmers. In *Futari wa Pretty Cure Max Heart*, her design evolves into a one-piece suit with a dark magenta vest and extra pink detailing, now covering her midriff following production adjustments. Energetic and impulsive, Nagisa loves food—especially chocolate and "yaki" dishes like takoyaki—alongside shopping and sunny days. Despite her athleticism, she enjoys girlish hobbies like collecting stuffed animals and feels self-conscious about her popularity; admired by female peers but envious of Honoka's frequent romantic attention. She often exclaims "Unbelievable!" ("Arienai!") when frustrated and declares "Lucky!" or "Unlucky!" based on circumstances. When others are threatened, a fierce sense of justice ignites her protective instincts. Key relationships shape her growth: Her bond with Honoka evolves from classmates to inseparable partners, with Nagisa unleashing heightened power whenever Cure White is endangered. She harbors a longstanding crush on Fujimura Shougo, Honoka's childhood friend, often flustering in his presence. At home, she shares a playful, caring dynamic with her younger brother Ryouta, defending him fiercely despite frequent squabbles and using a signature "Cobra Twist" to silence him. In *Max Heart*, she forms a protective friendship with Kujou Hikari (Shiny Luminous), prioritizing their personal connection over the Queen's resurrection. Her rapport with Mepple mixes constant bickering with deep mutual care, evident in her distress during their separations. Nagisa confronts significant trials, battling Dotsuku Zone agents and coping with the betrayal of ally-turned-spy Kiriya. A pivotal *Max Heart* moment sees Cure White captured, driving Cure Black to fight solo through enemies to rescue her, underscoring their reliance. The series concludes with Nagisa and Honoka losing their Pretty Cure powers after defeating Baldez but preserving their friendship as Mepple and Mipple return to the Garden of Light. Later appearances, like in the *HUGtto! Pretty Cure* film and crossovers such as *Soaring Sky! Pretty Cure*, show her as an adult retaining her original casual style but taller with longer hair. In *Pretty Cure All Stars New Stage: Mirai no Tomodachi*, she interacts briefly with other Cures like Hino Akane during group scenes, affirming her lasting franchise role.