Right before summer vacation, a beauty named Amamiya Shiina transfers into Yuuto's class. Yuuto and Shiina have had several fortuitous encounters before. They are surprised at how many times they've bumped into each other. Shiina plays the piano as well, and the genius-pianist, Haruka, is her idol. Being active, and successful in both academics and martial arts, Shiina quickly finds her place in the class. However, the news of the swim meet stumps her. Yuuto and Haruka finds out that swimming is Shiina's weak spot, and decide to help her out by giving her lessons. Will Shiina be able to master the art of swimming and compete in to the swim meet?