Akira Nishikiori is a seasoned officer within Japan's Cabinet Intelligence and Research Office who specializes in investigating supernatural phenomena. Initially deeply skeptical of magic and spirits, he gradually shifts to accepting the reality of supernatural forces. His role becomes that of a government liaison and bodyguard for the exorcist sisters Shoko and Maiko Ougi, bridging their spiritual work with official protocols. He supplies practical investigative support for occult crimes such as curses and possessions, using conventional police tactics and resources to complement the sisters' abilities. Over time, he evolves into a reliable ally and committed protector, often serving as the primary physical combatant against hostile entities. He partners with fellow exorcist Tsukasa Kenmochi, and their dynamic blends professional coordination with occasional friction.