TV-Series
Description
Shunkō Kubo, a Gothic fiction writer, begins as a secondary character but emerges as the primary perpetrator orchestrating the dismemberment crimes. His distinctive habit of perpetually wearing gloves is noted by multiple witnesses during abduction accounts.

Kubo is the son of Hyōei Terada, leader of the "Onbako-sama" cult which preaches supernatural beliefs. His involvement in the cult provides cover for his actions, influenced by his father’s fraudulent practices as a fake *onmyōji* (spiritual mystic).

His descent into violence ignites during a chance train encounter with Noritada Amemiya, guardian of Kanako Yuzuki. Amemiya reveals Kanako’s severed head, mechanically sustained inside a box by Dr. Kōshirō Mimasaka’s methods. Witnessing this horrific spectacle triggers Kubo's obsession with replication.

Inspired by Kanako’s state and his own literary fascination with the grotesque, Kubo abducts young girls—specifically daughters of his father’s cult followers—to obscure his motives. He confines them in an abandoned temple, attempting surgical head severance and mechanical sustenance inside crafted boxes. These failed experiments lead to the discovery of the girls' boxed limbs scattered across locations.

Kubo’s published fiction becomes a critical clue. Akihiko Chūzenji deduces his guilt by analyzing the disturbing themes in Kubo’s stories, recognizing them as reflections of the crimes.

Confronted at the abandoned temple by Detective Bunzō Aoki, Kubo flees and seeks Dr. Mimasaka at his research hospital, demanding knowledge to perfect his methods. Mimasaka instead subjects Kubo to the same procedure, severing his limbs and preserving only his head in a box.

In the climax, Kubo’s boxed head is wielded as a weapon. When Mimasaka attempts escape with the box, Kubo bites his neck, inflicting a fatal injury that causes Mimasaka’s death.

The anime adaptation incorporates sequences of protagonist Tatsumi Sekiguchi reading Kubo’s fiction, strengthening the link between Kubo’s writing and psychology. It further expands the wartime experimentation background of Chūzenji and Mimasaka’s research unit, providing darker context for the scientific horrors Kubo sought to replicate.