Tokiya Osada is a human character who appears in the 2023 film The Birth of Kitarō: Mystery of GeGeGe. His background is marked by a violent death at the hands of his own grandfather, Tokisada Ryūga. Tokisada used a forbidden Kidō technique to forcibly expel Tokiya's soul from his body, effectively murdering him in order to steal his youthful physical form for himself.

Following this event, Tokiya's spirit existed in a state of death. Seventy years after the destruction of a location known as Nagura Village, the spirit of Sayo Ryūga appeared before Tokiya in the form of a Kyōkotsu and escorted him to the afterlife. This action defines his primary role in the story, which is as a victim of his grandfather's cruel ambition whose lingering soul is finally laid to rest by another member of his family.

Concrete details regarding Tokiya Osada's personality and personal motivations are not documented. His development is primarily defined by this transition from a murdered soul to one that is guided to the afterlife. His key relationships are with his grandfather, Tokisada Ryūga, who is his murderer, and with Sayo Ryūga, who facilitates his final journey.

In terms of abilities, after his death, Tokiya Osada gained the physiology of a Kyōkotsu. This transformation granted him characteristics typical of such a being, most notably the power of invisibility.