Yato, also called Yasha, is a demon boy initially antagonistic towards Kanna. He tries to steal her mother's keepsake bracelet, believing it serves his objectives. He descends from a lineage of exceptionally fast-running demons stripped of their deity status by Ōkuninushi, the supreme deity of Izumo-taisha Shrine, a demotion fueling his motivations.

After an initial confrontation and winning a race challenge against Kanna, Yato shifts from adversary to reluctant companion. He joins Kanna and the rabbit messenger Shiro on their quest to collect feast offerings from shrine deities across Japan for delivery to Izumo, his inherent speed proving invaluable.

A significant development occurs when the group encounters an imposter deity mimicking Kanna's deceased mother. Yato discerns the deception and confronts the entity, declaring the real mother would never manipulate others. He intervenes to shield Kanna from the imposter's malevolent influence, sustaining injuries and demonstrating growing protective instincts and loyalty.

Later, upon meeting Ōkuninushi after completing their mission, Yato advocates for Kanna's deepest wish. He requests the deity use his matchmaking powers to reunite her with her mother, highlighting his evolved empathy. Ōkuninushi declines, explaining resurrection is impossible. Yato concludes his journey by returning to Tokyo alongside Kanna and Shiro.