Dubbed the “Detective Prince” by Persona 4's media outlets, Naoto is introduced before being named as a 'Slender Young Man'. After being thrown into the Midnight Channel, it is revealed that Naoto is female. The references to gender in her character-arc often leads fans to surmise that Naoto might be transgender, or at least primarily masculine-presenting considering that she continues wearing male clothing for the rest of the original game and Arena. (During the prologue in Golden, however, she's shown to be much more comfortable presenting herself as a woman.)
In Naoto's dungeon, however, the characters learn the truth about the way she thinks. After always being treated as inferior by the police force of Japan, not just because she's a woman but also because she's a teenager. She modeled herself after her idols in old detective movies, becoming an expert detective and hiding her femininity, and talking like an adult as much as possible. She resents the fact that detectives, unlike regular police officers, are quickly brushed aside soon after they have solved a case. In spite of her reputation as a prodigy detective and her determination to help out, she is treated like a child by members of the police department. Her determination to become a detective comes from both her deceased parents, who were great detectives in their day, and the line of detectives carrying the Shirogane name.
Naoto's dungeon is the "Secret Laboratory", which could represent Naoto's personality; even though she acts mature for her age, deep inside she harbors a childlike urge to be accepted by the adults who do not view her as their equal. When the Investigation Team reach both Naoto and her Shadow, it is implied that Naoto planned to be kidnapped and thrown inside the Midnight Channel in the first place. Naoto's shadow is seen to be taunting and berating Naoto over yearning to be like the "detectives like in the stories", and for secretly feeling lonely but being unwilling to admit it. A realization is made when it is revealed that Naoto is, in fact, a girl. This is because Naoto remarks "females aren't very befitting as detectives." Naoto's Shadow mockingly urges her to undergo a sex change, or "An alteration of the body," so that her male co-workers would treat her differently. After the Investigation Team defeats her shadow, Naoto comes to terms with the fact she needs to accept herself for who she is, which becomes more apparent in her social link.
Naoto should be noted as the only person who's Persona has no apparent weaknesses to elements, making it a strong choice. Naoto can be described as a "Jack of all trades", not being a bad character, but not specifically a good one. It's clear that she is to be used as a caster character, but one who focuses on Light/Dark/Almighty attacks. In addition to this, Naoto gets the powerful "Vorpal Blade" attack, dealing heavy physical damage multiple times. Naoto's downfall is the lack of real use and lateness ingame. While she may appear to have a high pool of SP, this is only regulated by the incredibly high cost of her special attacks. Her special attack knocks all enemies down. Despite this, Naoto is a strong character, and when her persona evolves from Sukuna-Hikona to Yamato-Takeru, her strengths become blocked, and also gains a resistance to fire magic.
The player can choose to have a romantic relationship with Naoto. Her social link involves a Phantom Thief leaving her letters for her to find certain items. All of the items being found by Naoto and Yu Narukami are detective devices she created in her childhood to use in investigations. The phantom thief is then revealed to be Naoto's grandfather's plan to make her mystery hunting motives return from carrying on the Shirogane name.
Max Social Link
According to her grandfather, Naoto's original reason to her passion to find the truth was through constant investigating. If the player goes down the romantic route with her, Naoto asks Yu if he prefers her with a low or high voice. If the player chooses a high voice, on Christmas Eve she will bring along a female Yasogami uniform in addition to her default clothing. In the Japanese version of the scene, Naoto asks if Yu minds that she still uses masculine pronouns (僕, "boku") to refer to herself.
After completing the social link, Yu receives a Watch from her. It gives the player the ability to create Norn once the Fortune Arcana has reached maximum level.
Persona 4 Arena
In Persona 4 Arena, Naoto continues her detective work and is hired for a special assignment by the Japanese Secret Police not long after the conclusion of the Inaba murder case. She is tasked with working as an observer during the transport of special cargo that is property of the Kirijo Group. However, she witnesses the cargo being stolen as it's due to be loaded onto the plane and tags the getaway vehicle with a tracking device. She is subsequently requested to trail after Mitsuru's team when they go to Inaba, leading her to follow them back into the TV world, where she becomes an unwitting participant in the P-1 Grand Prix.
- Shield of Justice (B + D) [P] : Naoto sends forth an immense shield that blocks attacks.
- Counter Shot (A or B or C or D): After blocking with Shield of Justice, the opponent will be hit with a small, melee range burst of energy.
- Counter Shot EX (6A or B or C or D): After blocking with Shield of Justice, Naoto sends a projectile towards the opponent.
- Double Fangs (236A or B) [SB] : Naoto kicks the opponent, and goes into Aim.
- Aim (214A or B) [SB] ::Naoto goes into her Aim stance.
- Snipe (Front) (A): Naoto shoots her opponent five times in her front direction.
- Snipe (Ricochet) (B): Naoto shoots the ground five times while the bullets are propelled upwards.
- Snipe (Anti-Air) (C): Naoto shoots towards the air five times.
- Cancel Aim (214A): While in Aim, Naoto cancels her stance.
- Hair-Trigger Megido (214C or D) [SB / P / AIR]: Naoto sets a detonator on the ground or in mid-air, which drops the opponent's Fate Gauge down if it connects. If Naoto is hit, the detonator disappears.
- Anti-S SP Pistol alpha (236236A) [A]: Naoto jumps backwards and fires several bullets from her assault rifle, muting the opponent.
- Anti-S SP Pistol beta (236236B) [A]: Naoto shoots a violet bullet from her shotgun, forcing the opponent's Fate Gauge down by a lot.
- Hamaon/Mudoon (236236C / D) [P]: When the opponent is at 0 with their Fate Gauge, either move will kill them instantly. Hamaon takes the place of a beam of light from the ground, Mudoon is a black smog that comes from the air.
Awakened SP Skills
- Raid (214214A or B then while walking, A or B): Naoto attacks her opponent by shooting a barrage of bullets.
- Critical Shot (214214A or B then while walking, C or D): Naoto kicks the opponent with a kick that bounces them all around the walls.
- Judge of Hell (222C + D) [P]: Naoto flips her pistol in the air, aims at her opponent and performs a fatal shot.
Persona x Detective
Naoto will star in the light novel Persona x Detective, set to come out in Japan Spring 2012. Now in her last year of high school, she still works as a detective investigating a series of disapperances. It features a different school setting than Persona 4.