In a small fishing village, a gloomy middle school student named Kai meets a mermaid named Lu.
A young piano prodigy, Yuri Kashiwagi, returns to her hometown after several years and joins a middle school to mentor the choir group.
Hayakawa Yui is a young girl whose biggest quality is to be a fast runner. She accidentally travels through time up to the Sengoku Era and falls in love.
