Keiji Mogami

Keiji Mogami (最上啓示, Mogami Keiji) is an immensely powerful evil spirit who was once an esper famous for being "The Greatest Psychic of the 20th Century."

Appearance
While still alive, at his physical peak, Mogami was a regular looking man with flat dark coloured hair and small lines under his eyes. He normally wore a white shirt with green pants and a green blazer. As he got older, his age and world-weariness were visible as he started getting wrinkles.

As a spirit Mogami took on many different forms. For example, when confronting Mob for the first time in his mindscape he appeared just as he did as a human. However, oftentimes this form was underlined by hollow cheeks, dark eyes, and sluggish posture. While watching Mob in his artificial world he would manifest as different small animals such as a crow, a moth, or a caterpillar to spy on him. During his battle with Mob he also appeared as some sort of ghostly wraith of dark green smoke with red eyes, and later as a being composed completely of red and black energy. When he was released from Matsuo's canister by a Claw soldier, he briefly took on the form of the shadow of the girl he possessed, Minori Asagiri. He also temporarily created a massive tree-like body for himself out of Minegishi's plants at one point.

Personality
Keiji Mogami is a very bitter man, sick of the greed and selfishness of humanity. Because of the private dealings he did while alive, he has lost his moral compass and has become a twisted variant of his former self. After becoming an evil spirit, he vowed to use his power for his own intentions and fix the world by possessing people who appear to gather grudges around them. To that end, Mogami is willing to destroy a young girl's body and brutally impale her father to achieve his whims.

History
Mogami was born with the ability to see ghosts and other powers people dreamed of, so he initially did the world good by giving advice and helping people with their problems. To that end, Mogami became one of he most famous psychics and was the first psychic to be on Japanese television. However, his mother suddenly became gravely ill and the treatment was very expensive so Mogami needed money. Due to this, outside of the spotlight, he would take on assignments from clients to solve their supernatural problems and would even take assignments from the underworld to lay death-inducing curses on others. Despite the morally dubious assignments he was taking, he continued taking them in order to pay for his mother's treatment. His mother eventually died, returned as an evil spirit and revealed that the reason she died was because all of Mogami's actions had gathered "demons" around him, which meant that she suffered.

Since he no longer needed money, he stopped all his business with the underworld. Pondering the how much of a waste his life had been, Mogami resolved to fix the world and travelled around consuming evil spirits to cultivate his power for when he would eventually become an evil spirit. At one point, he encountered Dimple's group and annihilated them, with Dimple just barely escaping. He committed suicide 25 years prior to the start of the series, becoming a powerful spirit in the process so that he could torment the "evil people" of the world.

Keiji Mogami Arc
One of Keiji Mogami's attacks included entering the wealthy businessman Masashi Asagiri's mansion and possessing his daughter Minori Asagiri, a callous and spoiled girl whose troublesome behavior irked him. Masashi was forced to seal Minori in a protective room and lock her into a bed.

Masashi eventually hires literally hundreds of spirit detectives to help his daughter, including Reigen and Mob. When Reigen enters the cell to talk to her, Mogami tries to get him to believe that Masashi is the one who's been possessed and is acting irrationally - this convinces many of the exorcists, but not Reigen. He notices inconsistencies in Minori's speech, such as odd changes in tone of speech and knowing Reigen was a psychic before he even introduced himself as such. Unfortunately, the other exorcists do not believe him. The Mogami-possessed Minori breaks out of the cell, and Dimple recognizes him from a previous fight and warns Mob. Several exorcists try to exorcise Mogami and fail, and he goes on a rampage before being stopped by Mob's telekinesis. However, Mogami begins breaking Minori's body against the force of the telekinesis and forces Mob to let go of her. Jodo attempts to defeat him as well, but gets possessed by Mogami as well before he is knocked out by Reigen. Mob realizes he can't exorcise Mogami from Minori from the outside, but if he is to astral project into Minori's mind then he could have a chance. He temporarily lets Dimple have control over his body while he sends his spirit into Minori's body.

Mogami encounters Mob in a form similar to his human appearance, explaining that they are in a mind-based world of his own creation inside Minori. Mob is powerless to fight him and is subdued, being placed inside a world identical to the real one where he is tormented and mistreated by brutal and uncaring versions of real people in his life, including Minori herself. Over the course of what seems to be six months for Mob he is tortured while Mogami sends him subliminal messages, eagerly waiting for the boy to crack and become another malevolent soul like himself. It comes to a breaking point where Mob momentarily agrees and attacks the artificial Minori and her friends with his psychic powers, but Dimple enters the mind world as well and snaps Mob out of it. Mob realizes his mistake and begins to tell Mogami of the err of his ways. Infuriated, Mogami releases the legions of evil spirits he has assimilated over the years to attack Mob, who reaches 100% Courage and fights them off in a battle that tears apart the very fabric of the mindscape. Mogami himself personally attacks Mob, but is defeated in a powerful psychic blast. However, his evil spirits go ballistic without Mogami around to control them, and they brutally gang up on Mob again. Mob's ???% mode is initiated due to the stress and ???% completely erases the mind world, freeing Mob.

Back in the real world, the weakened Mogami leaves Minori's body in an attempt to flee, but is captured in a film canister by Matsuo. Matsuo would go on to name Mogami "Pudding-chan" and keep him as a dangerous last resort weapon.



World Domination Arc
When Matsuo appears to help Mob fight against Minegishi and a group of Claw soldiers, Mogami's container falls out of his jacket. Despite Matsuo's protests one of the Claw soldiers breaks the container, releasing Mogami. The powerful spirit sucks the life out of the Claw soldiers, and when attacked by Minegishi uses his own plants and chunks of concrete from the ground to form a massive tree-like monster. Mogami uses the monster to grab Minegishi, raising him into the air and slowly crushing him. Mob manages to convince Mogami to let him go, showing that Mogami has come to respect the young esper, and Mogami vanishes, leaving nothing but a large tree in his absence. His whereabouts after this incident are unknown, although Dimple suspects Mogami passed on for good.

Powers & Abilities
Mogami is one of the most powerful characters in the series. When he was alive as a psychic, he effortlessly defeated full power Dimple, a high-level evil spirit; and as an evil spirit, he easily overwhelmed Minegishi, one of the Ultimate 5. Mogami left such an impression on Dimple that Dimple suggested to Mob and Reigen to just leave when he found out that the evil spirit they were dealing with was Mogami. Although false, when Mob failed to exorcise him from within Minori Asagiri's body, Mob even claimed that Mogami might be stronger than he is. Despite all this, Mogami was no match for Mob at 100% Courage.

Evil spirits inside Mogami
Having absorbed them over his lifetime, Mogami's spiritual body was home to an unimaginable amount of malevolent souls. He collected so many that even he cannot control them all, and can only manipulate them if he releases them little by little. When Mogami was defeated by Mob, all the spirits inside him were unleashed and went out of control. The combined might of every single evil spirit was capable of overwhelming Mob at 100% Courage. They were swiftly defeated by ???% afterwards.

Quotes

 * "You cannot solve all problems with your kindness. Sometimes, you need to be strict to others."

Trivia

 * In the manga his death take place 25 years prior to the series, while in the anime it is 40 years.
 * The berserk evil spirits can be considered Mogami's equivalent of ???%. They were unleashed when Mob destroyed Mogami's vessel, and ??? was unleashed when the evil spirits destroyed Mob's vessel.
 * The berserk evil spirits are the only opponent that defeated Mob at 100%. Toichiro Suzuki came close but his fight against Mob got interrupted by him self-destructing, resulting in a draw.