Ryo Hamura comes from a military background, having worked as a mercenary before embracing a religious vocation. His physique bears the marks of combat experience: a muscular build and a prominent scar.

After a catastrophic earthquake shattered Tokyo and triggered societal collapse, he operates an orphanage within the ruined city. This orphanage faces a direct threat from the Koryukai crime syndicate, which aims to seize the property. Despite his role as a priest, Hamura retains formidable proficiency with weapons and combat tactics.

He works closely alongside Sister Saeko Kishima, who also possesses combat skills. Together, they utilize both defensive strategies and offensive actions to protect the orphanage and its children from syndicate attacks. Hamura contributes his strategic military experience during the group's assault on the Koryukai compound.

His character embodies the duality of spiritual calling and martial prowess, serving as an armed protector within the conflict against the criminal organization.