Tomisaburō Tengai, known as Tommy, stands as a steadfast ally to Shinichi Kuruma in their flight from genetically engineered pursuers. He wields psychic premonitions that alert him to imminent threats, specifically cautioning Shinichi against forming ties with Ayaka Sanders—a warning rooted in echoes of past calamities.

His sister, Maria Tengai, once hunted by adversaries for her identity as the Virgin Mary’s reincarnation, perished in Shinichi’s arms, igniting the "Great Destruction." This cataclysmic earthquake event ravaged Shinjuku, cementing his wariness of alliances and personal investment in the ongoing struggle.

The group’s retreat to his hometown transforms it into a provisional stronghold against their engineered foes. Tommy’s appearance is marked by a signature scarf and prominent eyebrows, traits as distinctive as his tactical mindset.

Guided by premonitions and hardened by loss, his strategies blend protective vigilance with survival-driven pragmatism, shaping pivotal choices throughout their harrowing journey.