Natsuki Sakuraba is a young detective employed by the Metropolitan Police Department. Her father, also a policeman, passed away, and his career inspired her to pursue law enforcement. She serves as a supporting character in the series, working alongside Inspector Koichi Zenigata and fellow officer Shintaro Kunikida. Her motivations are rooted in following her father's example and upholding justice. Within the story, she assists Zenigata in investigating various cases, often acting as a junior colleague who learns from his experience. Her key relationships are with Zenigata, whom she respects as a superior, and Kunikida, her close coworker. The series does not depict extensive character development, but she consistently demonstrates dedication to her duties. Her notable abilities include standard detective skills such as investigation, observation, and fieldwork.