Ojii, the deceased grandfather of the Kyan family, persists as a spirit dwelling within their home. Though no longer alive, he actively involves himself in the household's daily life. He remains invisible and imperceptible to outsiders.

His lingering attachment to domestic routines manifests in actions like sweeping the courtyard, activities noted as lacking practical purpose for a spirit. His presence underscores the seamless intersection of the supernatural and the ordinary within the Kyan household.

Ojii is Japanese, his bald head being a distinguishing physical trait. He shares the home with his granddaughter Nanafa Kyan, her grandmother who runs the "Kame Soba" shop, older sister Nao, and younger sister Kokona. Kokona's heightened sensitivity to supernatural entities allows her to perceive spirits like Ojii.

His background as a family patriarch remains defined by his current spectral role. His portrayal remains consistent as a benevolent, non-disruptive spirit integrated into the family's domestic environment, without significant evolution or expanded backstory documented in other media.