High school student Yohana Sakaki lives in a town where the Yashiro family, a powerful clan of Shinto priests, holds absolute authority over the spirits and evil entities that haunt the area. Orphaned and living with her grandmother, Yohana has distant ties to the Yashiro family but possesses no spiritual abilities and has resigned herself to an ordinary life. When her grandmother insists she attend a banquet at the Yashiro estate, Yohana accidentally falls into a pond. The commotion attracts the attention of a high-ranking Yashiro heir, who briefly seems interested in her but then dismisses her in favor of another girl who also fell in. Left soaking and unnoticed, Yohana is rescued by a mysterious, gentle boy named Chitose, who takes her to his secluded quarters on the estate. Chitose quickly recognizes that Yohana is a Rare Visitor, a human who has drunk water from another world and now holds divine power. As the Yashiro family takes Yohana under its protection, Chitose is assigned as her guardian and guide. Together they begin assisting with exorcisms and spiritual work, pulling Yohana into a hidden realm of gods, curses, and supernatural politics. Her awakening power and her bond with Chitose set the stage for a love story entwined with fate, as both must navigate the dangers and obligations of a world where the ordinary and the otherworldly meet.