Shadow Naoto is the Shadow of Naoto Shirogane which manifests after Naoto is thrown into the TV World. Shadow Naoto's human form wears a large, oversized lab coat. After being denied by Naoto, the Shadow transforms into a robot. Shigenori Soejima designed the robotic parts to look old-fashioned and give off the feeling of older Sentai shows.[1]
On September 15th, after being thrown into the TV World, Naoto's repressed feelings cause a Midnight Channel broadcast where a version of Naoto in a lab coat welcomes viewers to a program called "The Great Experiment of the Century: Genome Project" where it will undergo a body alteration surgery.
In the basement of the Secret Laboratory, the Investigation Team finds the real Naoto alongside Shadow Naoto, which was born from Naoto's repressed feelings. Naoto has been waiting for the team to show up and refers to the Shadow as an annoyance. The Shadow begins throwing a tantrum, telling Naoto not to leave. The Shadow's childishness isn't just for show; this is also Naoto's truth because no matter how many cases the Detective Prince solves, people will continue to treat Naoto as a child. Furthermore, while Naoto looks up to adult male detectives from fiction and aspires to be like them, the Shadow reveals that Naoto is unable to do so as Naoto is, deep down inside, still a child and also a girl.
The Investigation Team are surprised to hear that Naoto is a girl as they had believed Naoto to be a boy this whole time. Naoto verbalizes that she won't throw a tantrum over this, and Shadow Naoto mocks her as that phrase was something others used to say to her and surely made her cry. Shadow Naoto reassures Naoto that there is no need to push herself anymore now that she can undergo body alteration surgery, saying that it understands how she feels since they are the same person. Naoto denies her Shadow after hearing this. Chie tries to stop her, but Kanji encourages Naoto to do it. After, Shadow Naoto transforms into a robot that attacks the group and even uses skills that cause aging. Following the battle, Naoto expresses that she needs to accept her childish Shadow for who it is instead of becoming an adult man. She accepts her Shadow as a part of her, and it transforms into the Persona Sukuna-Hikona.