Naoto Shirogane (The 2000-IQ Killjoy Detective) is one of the main characters in Persona 4, the 5th main installment in the Persona series and one of the playable characters in its fighting game sequels, Persona 4 Arena and Persona 4 Arena Ultimax. Originally, Shirogane was the main protagonist of non-canonical spin-off Persona x Detective Naoto prior its canonization being debunked since the release of Ultimax.
She returns as one of the Season 1’s DLC playable characters in BlazBlue Cross Tag Battle.
A young detective working alongside the police in Inaba. Part of the Shirogane family's long line of detectives, she too wanted to become one, but living under the impression that only men can excel in the profession caused her to disguise herself as a man. During the murder case in Inaba, which Naoto and the rest of the police were investigating with little success, she picked up on the fact that all of the victims appeared on television before being kidnapped. Thus, she allowed herself onto a TV interview and waited to be kidnapped, hoping to discover more about the case. When Naoto was taken and forced into the TV World, she found her Shadow inside the Secret Laboratory, who revealed to the Investigation Team about her true gender and fear that once the case is over, the police will stop caring about her because she’s perceived as an immature child. Upon accepting her fears instead of attempting to deny them, Naoto gained her Persona, Sukuna-Hikona, and chose to work with the Investigation Team for the rest of the case.
A few months after solving the Inaba serial murder case, Naoto joins the Interpol, where she unexpectedly meets the Shadow Operatives Aegis and Mitsuru Kirijo. They end up working together to investigate the P-1 Grand Prix Tournament that is taking place inside the TV World. At some point as an Interpol agent, Naoto began to research about the history of Dark Hour, which happened in many years ago during the events of Persona 3. While in the middle of research, Dark Hour suddenly occured in mostly centered in Inaba, and Naoto realize the P-1 Tournament is still on, under the final season titled P-1 Climax. Fearing the deadly outcome, she rushes to find her friends, while also reunite with the robotic first victim of original P-1 and pre-reformed Kirijo’s test subject, now turned an Operative member Labrys, informed that Aegis, Mitsuru, and Akihiko Sanada are somehow kidnapped to lure both Inaba’s Investigation Team and all Shadow Operatives to the trap and outcome set by mastermind, who revealed himself as Sho Minazuki.
- Shirogane has color palettes of the following characters: Ken Amada (Persona 3), Hazama Honoka, Yukino Mayuzumi (Persona 2), Bloody Chaos (Under Night In-Birth), and Pyrrha Nikos (RWBY).
- Sukuna-Hikona has color palettes of the following characters: Ken Amada, Hazama Honoka, Durga (Persona 2), Bloody Chaos, and Jaune Arc (RWBY).
- The Persona universe’s Naoto should not be mistaken for another Naoto from BlazBlue universe, whose last name is Kurogane. Even with Kurogane’s inclusion in this game, both Naotos still don’t have their Western-based Versus/Lifebar/Win/Victory names updated to avoid their first names clashing and being mistaken from each other's identities, unlike in Bandai Namco’s Tekken Tag Tournament 2 on both Marshall and Forest Laws. Instead, they can only be recognized by their series color on Versus/Victory names.
- As of full version Season 2, the new lifebar background on each two Naoto can be identified by the series’ color representation.
- In Persona 4, Chie Satonaka mentions that Naoto reminds her of a detective from a movie starring Raidou Kuzunoha, a major character in the Devil Summoner series of SMT games.
- Naoto's Title The 2000-IQ Killjoy Detective Part of her title in Japan (IQ2000のKY探偵 Ai Kyū Nisen no Kē Wai Tantei) "KY" is a Japanese slang abbreviated from the phrase "kūki ga yomenai" [空気が読めない, unable to read the atmosphere] which means someone is acting improperly in the wrong occasion. Yosuke uses this slang on Naoto during their school trip to Tatsumi Port Island in the club in the Japanese version.