One day, three second-year middle school students — Kazuki Yasaka, Toi Kuji, and Enta Jinai — meet a kappa-like creature named Keppi, who is the self-proclaimed heir to the throne of Kappa Kingdom. Keppi forcibly takes the students’ shirikodama (a mythical organ kappa steal through a person’s anus) and they are transformed into kappa. Keppi informs them, “If you want to return to your former selves, you need to connect in ‘that way’ and you must bring me the shirikodama of zombies.” At the same time, two policemen, Reo Niiboshi and Mabu Akutsu, try to do something at the police box where they are stationed. – ANN
Streaming: Crunchyroll and Funimation
Episodes: 11
Source: Original
Episode Summary: In Asakusa, images of the Kappa yokai abound. But little did Kazuki, Toi, and later Enta suspect that the golden kappa statue within the local shrine housed inside it a real, live kappa. After running into Kazuki again by accident, Toi’s violent defense of his own illegal activities knocks the statue off its base; when they return to the scene of the crime later on, Prince Keppi of the Kappa Kingdom appears before them in a poof of purple smoke. When the boys mistakenly refer to Keppi as a frog, he punishes them by stealing their shirikodama (an organ in the anus housing human desires) and turning them (and later Enta) into kappa.
Their ticket back to humanity relies on their ability to team up and steal the shirikodama of zombies – poor humans consumed by their own artificially-augmented desires. The only catch is that, once doing so, the three boys’ own deep, dark secrets are revealed to one-another. As the trio completes the Sarazanmai, Kazuki’s secret is thrust out into the open. This is embarrassing, but could this be a way for him to seek the connections he desires?