Detective Ozaki serves within the Tokyo Metropolitan Police Department, directly assisting Deputy Chief Kyoko Ishihara. He investigates yakuza activities, particularly those connected to Akira Hojo and the Sagara Alliance. Ozaki knows the underworld intimately, maintaining a long-standing professional acquaintance with Tokai, a high-ranking Sagara Alliance yakuza member. Despite this connection, Ozaki remains committed to his duties as a law enforcement officer.

He is characterized by facial hair, frequently wears sunglasses, and is a smoker. Ozaki operates within the police hierarchy, often reporting to or aiding Kyoko Ishihara in her cases. His interactions with Tokai reveal a complex professional dynamic, acknowledging their shared history while upholding the law. Ozaki's investigative focus centers on gathering intelligence and evidence concerning organized crime operations affecting Tokyo.