|A young investigator caught up by evil.|
|Voiced by:|| Satoshi Takemura |
During his time as a student he wears a distinct school uniform that consists of dark greens pants and a similarly colored zipped jacket over a white shirt.
During his time as a student, Yamanishi has an intimate relationship with his older professor and school nurse Reika Kitami. He is devastated when she leaves the school and transfers to the another school. As she says goodbye, the boy desperately clings himself to her in tears. Kitami tells him that she wants him to give her good memories of the school and they passionately have sex, Yamanishi's first time. It is an experience they both never forget.
A mysterious murder case
Later in life, Yamanishi pursues a career as a police investigator. He and his partner are sent to investigate a mysterious case on the roof of the Academy. A female student and male teacher are found dead, but the male's body has burned to a crisp, whereas the girl is completely intact. Puzzled about the complexity of the case, Yamanishi sees Toru Yuge arrive on the scene. The chief of Tokken, a special investigations agency, takes charge of the case and dismisses the police officers.
As Yamanishi makes his way downstairs, he spots a female Tokken agent going back to the roof. He decides to follow her and witnesses her and Yuge being attacked by a mysterious robed girl floating over them. She launches a powerful lightning bolt down into the roof's pool. In the blinding flash, Yamanishi suddenly comes face to face with an image of Reika Kitami, the professor he had a crush on in his teens.
Time in the hospital
Later, his partner visits Yamanishi in the hospital to show him the autopsy of the student girl found on the Academy roof. He argues that although the police is no longer formally in charge of the case, they still have the jurisdiction to get a report on the autopsy. As they enter the examination room, however, the student girl that was dead just moments ago has mysteriously come back to life. She cheerfully smiles at their shocked faces while staring out the window.
Yamanishi later rescues Aki Ichikawa, a young Tokken agent also brought into the hospital. She is sexually assaulted by the vice-principal of the Academy, who has been possessed by a demonic entity. Yamanishi hears Aki scream when he goes out to get a drink from a vending machine and makes his way to her room. He sees the vice-principal stabbing Aki with a small knife and swiftly knocks him out by first throwing his soda can at him and then hitting him with a metal pole. Just when Yamanishi wants to call for a doctor to help Aki, a mysterious light shoots out from the girl's body, pulling the knife out and completely healing her wound.
After leaving the hospital, Yamanishi files a report on his experiences to his police chief. But he dismisses it as nonsense and takes him off the case. Yamanishi angrily resigns his commission and turns in his gun, cuffs and badge to the chief before walking out without saluting. Outside, his partner gives him the address of Tokken, informing him that he and chief Toru Yuge used to go to the police academy together and that the man left for the same reasons as Yamanishi.
Yamanishi makes his way to the Tokken headquarters where Yuge allows him to investigate the files related to the case. To his surprise, Yamanishi discovers that his boyhood crush Kitami transferred away from his school in the same year the Tokken agent Kurumi Imari he saw in the hallway enrolled at the Academy. He then reminisces on his relationship with Kitami and their final encounter.
Corrupted by evil
Imari joins Yamanishi while he is researching and offers him coffee. Unbeknownst to Yamanishi, however, the drink has been drugged with some sort of stimulant. Imari quickly closes the files on the computer after realizing Yamanishi has been researching her past. Not long after, the drug starts taking effect and Yamanishi starts feeling faint. Imari then reveals herself to be Kitami, causing Yamanishi to again desperately cling himself to her as he reminisces about his last romantic encounter. He then passes out.
Soon after, still completely absorbed in his memories, Yamanishi continues to project them on one of Kitami's followers Saki Kiriya, whom he now believes to be Kitami herself. The girl willingly offers her body to him and they proceed to have intercourse, surrounded by Imari/Kitami and her devotees. The witch engages in a ritual by cutting her hand and has Yamanishi's semen collected in a golden chalice. She mixes it with her blood and feeds it to him, corrupting Yamanishi's mind and body into a diabolic sexual perversion that causes his penis to grow to a monstrous size.
Imari/Kitami then forces her other disciple Kaori Saeki to have sex with him. The woman eagerly makes love to him at first, but Yamanishi violently and relentlessly rapes her in his crazed possession. As he climaxes, a demonic marking appears on his neck. Moments later, a magic barrier briefly forms around them before Imari/Kitami dispels it.
Yamanishi is left behind sleeping on the couch of the Tokken headquarters. He is comforted by Aki after she discovers it was him who saved her in the hospital. However, still under the influence of evil, he strangles her with his belt after waking up and tries to rape her, but is blocked by some sort of protection spell.
The final ritual
He is picked up by Saeki soon after and brought to the Academy basement to participate in a vast orgy. He assaults Hiroko Takashiro, one of Kitami's enemies, as the witch and her adversary Jody Crowley battle. Jody is victorious, and at the direction of Crowley's guards, Yamanishi next rapes Saki Kiriya - who is being used in Jody's mysterious ritual.
Soon after, Toru Yuge and Takashiro attempt to stop the ritual. Jody compels Yamanishi to attack Yuge and he swiftly grabs him from behind to hold him down. However, the Tokken director manages to break free and successfully interrupts Jody's plans by firing his pistol at a black magic tome that has emerged during the ritual.
Following the night, Yamanishi's mind and body are returned to normal and he later buys Takashiro and Yuge a snack from a street vendor.
Personality and traits
- For an overview of all 58 images of Naoto Yamanishi, see Images featuring Naoto Yamanishi.