Kitarō’s father, once a member of the Ghost Tribe, succumbed to illness and was reborn as a sentient eyeball after his corpse decayed. In his former humanoid life, he wedded Iwako and fathered Kitarō. His human existence intertwined with a 1950s village under the Ryuga clan’s dominion, where he searched for his disappeared wife and unraveled secrets of "M," an enigmatic medicinal substance. His probe into the village’s spectral phenomena and the Ryuga’s cruelty culminated in catastrophe, ending his mortal life and triggering his rebirth.

Now spectral, he preserves vast yōkai wisdom and an unshakable bond with Kitarō, assisting him in arbitrating disputes between humans and spirits. His diminutive, fragile form belies a steadfast resolve, evident in his devotion to mentoring and safeguarding his son. He routinely soaks in modest vessels—a nod to his meticulous nature—and retains a taste for sake.

His past ties to the Ghost Tribe’s hidden society, their near-annihilation, and Kitarō’s posthumous birth from Iwako’s grave underscore the family’s sorrow-laden legacy. In his spectral state, he allies with figures like the human Mizuki to combat supernatural menaces, mediating between mortal and spirit worlds.

His arc spans a grief-stricken widower seeking truth to an ethereal mentor wielding ancestral knowledge and ghostly prowess. Beyond guiding Kitarō, he embodies the Ghost Tribe’s enduring legacy, acting as a living chronicle of mystic history essential to quelling yōkai discord.