After accidentally breaking a statue of a kappa at a shrine in Asakusa, middle school student Kazuki Yasaka encounters Keppi, heir to the throne of the Kappa Kingdom. He, along with his classmates Toi…

Keppi gives the group a Dish of Hope as thanks for helping him, which grants one wish to whomever possesses it, and informs them that they can earn more plates by defeating more zombies. Kazuki explai…

Enta, who has a crush on Kazuki, wishes to earn a dish so that Kazuki will return to playing soccer with him. Reo and Mabu extract the desires of Otone's boyfriend (who, unbeknownst to her, is a seria…

Kazuki asks for Toi's help to kidnap Sara and so that he can take her place during a meet-and-greet that Haruka plans to attend. Toi's backstory is revealed through a flashback – after his parents die…

Toi attempts to kidnap Sara, though she evades him by transforming into a kappa, exposing Kazuki's crossdressing to his family. Kazuki reveals that he is adopted, and that he blames himself for Haruka…

The group rescue Haruka after he is kidnapped by Reo, and are transformed back into human form. Keppi explains that Reo and Mabu are agents of the Otter Empire, who have been at war with the Kappa Kin…

In a flashback, Mabu is brought back to life with a mechanical heart transplanted by Otter, though Reo believes that Mabu is merely a re-animated facsimile. Chikai's criminal dealings force him to fle…

Chikai and Toi make preparations to leave the city. Enta returns the Dishes of Hope to Kazuki, but they are confronted by Reo and Mabu, who intend to use the dishes to restore Mabu. Reo shoots Enta, a…

Keppi transforms a hospitalized Enta into a kappa so that he and Kazuki can recover the dishes. Reo witnesses Otter performing sexually-charged "maintenance" on Mabu's heart; when he intervenes, Otter…

Kazuki, Enta, and Keppi encounter Dark Keppi, the corporeal form of half of Keppi's shirikodama held by the Otter Empire. Otter, having learned of Reo's plan to use the dishes on Mabu, transforms Mabu…

Toi begins to destroy his connection to Kazuki and Enta, but ultimately chooses to preserve it. Keppi fuses with Dark Keppi, with assistance from the group and a revived Reo and Mabu, and defeats Otte…