Domon

Domon is mature, disciplined and protective of the younger officers under him. He understands Senji's anger but refuses to accept brutality simply because the intended victim is a criminal.

He teaches Senji that strength carries responsibility. When Senji nearly kills a defeated opponent, Domon stops him and insists that crossing that line would make him no better than the people he fights.

Domon also has a dry, paternal manner toward his team. His willingness to shoulder danger for younger colleagues embodies the adult responsibility he repeatedly tries to teach Senji.

Domon is an ordinary human police officer with no Branch of Sin. His abilities come from professional police training and practical combat experience in the violent environment left by the Great Tokyo Earthquake.

He is capable enough to serve in the special police group combating organized gangs in the ruined areas of Tokyo.

Domon appears primarily in the material exploring Senji's life before Deadman Wonderland. He serves with Senji, Akira Shindō, Tōshirō Kan and Momoi while confronting criminal groups in Tokyo.

He repeatedly intervenes when Senji's aggression threatens to cross the boundary between policing and execution.

When criminals associated with Ikazuchi Akatsuki challenge Senji, Domon and the other officers go to the confrontation without him in an attempt to protect him. Senji arrives after the team has been slaughtered; Domon survives long enough to give him one final lesson before dying from his injuries.

Kiyomasa Senji is Domon's subordinate, friend and protégé. Domon's lessons strongly influence the principles Senji carries into his later life.

Akira Shindō, Tōshirō Kan and Momoi serve alongside Domon and Senji in the same police team.

Ikazuchi Akatsuki is associated with the criminals whose attack results in the destruction of Domon's police team.

Keigo Ugachi is another criminal whose confrontation with Senji prompts Domon to intervene and prevent his subordinate from becoming a killer.