Ark Academy was chosen as a model school for inter-species students. A teacher came to the school to give a one-day “assistance” to the idol group “Aquamarina” to which Elio, a mermaid enrolled in the school, requested… “Sorry, coach. It was only supposed to be one day…” During the tour, which lasted several days, it was a “happy bus tour where you can have sex with active idols from morning to night!” Ella, a tanned gal idol who boasts huge breasts. Elsie, a natural loose and fluffy idol. And Elio, who is slender and delicate and tries her best to get pampered. The teacher, who spends his days immersed in ○○○○ with three beautiful idols, is bewitched by the mermaid’s singing voice and his reason melts away… “A bus tour where you can have sex with three active mermaid idols from morning to night” is ready to go!? The bus is shaking even when it’s stopped, isn’t it?