Yamato Amanokawa lives in the Shichifukujin neighborhood’s Amanogawa household alongside his sister Himi Amanogawa and parents Nami and Mikoto Amanogawa. Five Engimon share the children’s room—Haruo, a papier-mâché dog; Kin-chan, a goldfish paper balloon; Hebikura, a bamboo snake; Chief Daruma, a daruma doll; and Koume, a Kokeshi doll—all perpetually watching over Yamato and Himi.

The pivotal moment unfolds when an unfamiliar beckoning cat Engimon appears. Himi vanishes after pursuing this mysterious entity, prompting shock from Yamato as Haruo and the other Engimon suddenly animate. Yamato allies with them, embarking on a mission to locate and rescue his missing sister. This rescue operation forms the core of his documented journey.