A Fish Is to Water as a Genius Is to [X].Uruka Takemoto, Nariyuki's middle school friend, is an outstanding swimmer nicknamed “Shimmering Ebony Mermaid Princess” with a recommendation for a Sports Scholarship. Unfortunately she is failing most of her subjects. To ensure she earns the scholarship the Headmaster asks Nariyuki to tutor her. At first, Uruka refuses to study, until she learns about Fumino and Rizu. Having had a secret crush on Nariyuki since middle school she immediately joins their group. Rizu is given 24 hours to rewrite an essay about civilisation, and asks for Nariyuki's help; with Uruka joining them after hearing Nariyuki is alone with Rizu...