TV-Series
Description
Kōsuke Mikado is a shy bookstore clerk with relatively short dark hair, long thin eyebrows, and thin-framed glasses. He possesses the lifelong, terrifying ability to see ghosts and spirits, which he actively avoids and keeps secret. His fearful disposition toward the supernatural makes him easily influenced.

Mikado grew up with his mother after his father vanished when he was four, leaving only a jewelry box. No one, including his mother, remembers his father's name or face, suggesting supernatural erasure linked to this past trauma, compounding his anxiety. His life changes when exorcist Rihito Hiyakawa detects Mikado's power in the bookstore. Hiyakawa forcibly recruits Mikado as his assistant, calling it "destiny." Despite Mikado's initial reluctance and primal fear of ghosts, he becomes involved in Hiyakawa's exorcisms and supernatural investigations, particularly cases involving curses and unsolved murders connected to a cult.

Over time, Mikado evolves from passive fearfulness into an active participant. His abilities prove essential during exorcisms, acting as a "catalyst" or conduit for Hiyakawa's powers. Their spiritual merging during these sessions is intensely intimate, leaving Mikado physically drained and disheveled. This bond deepens into a complex interdependence; Hiyakawa exhibits possessiveness and jealousy over Mikado's spiritual connections to others, while Mikado develops a compulsion to protect Hiyakawa, even when confronting unsettling truths about Hiyakawa's violent past with the cult that abused him.

Mikado's empathetic nature positions him as a healing figure. He chooses to aid teenage necromancer Erika Hiura, manipulated by the cult leader "Sensei," despite Hiyakawa's indifference, recognizing her as a pawn. His investigations gradually reveal connections between the cult, his missing father, and the mysterious jewelry box, driving him to confront "Sensei," who harbors specific hatred toward him.

In the live-action film adaptation, Mikado's character development and backstory are condensed. Key elements like his father's disappearance, the jewelry box, and the depth of his spiritual bond with Hiyakawa are omitted or minimized, reducing his motivations. The film also removes nuanced, potentially romantic aspects of their relationship present in the source material and supporting characters influencing Mikado's growth.