Sealed inside a room for 13 years, Mashiro Kamitsuka spends her days watching over the divine beings that dwell inside her hair. As the shrine maiden of the Kamitsuka clan, she must take proper care of her long hair and serve as a resting sanctuary for the deities who have lost their strength.

Even though she has patiently waited for the deities to leave her hair, none of them have done so since her confinement. One morning, she hears a mysterious voice that leads her outdoors, where her relatives try to coax her back inside. Unwilling to return, Mashiro professes her wish out loud, causing the god of fire Hinokagutsuchi, "Hinokagu," to appear. With the powers of Hinokagu and her faithful servant Hayate assisting her, Mashiro escapes the family estate and takes refuge in a run-down shrine.

Alhough Mashiro, Hayate, and Hinokagu try to live a normal life together, the Kamitsukas do not plan to leave them alone and continue to expand their means of punishment. These new circumstances, however, are not entirely disadvantageous for the trio. By breaking free from familial chains, Mashiro soon learns more about her purpose as the Kamitsuka shrine maiden, the deep-rooted secrets within her family, and the troubled past of the god who changed her life.