It's a Sunday in June. Kohei and the treasurer, Seiichiro, are swamped with work to complete a plan laid out by the student council president, Iori, "Let's make the opening of the pool exciting." During which, Kohei becomes aware that it is Erika's birthday...
６月の日曜日。生徒会長・伊織が思いついた『プール開きを盛り上げよう』という企画の実行のために、孝平と財務の征一郎は監督生室で仕事に追われていた。
そんな中、孝平は今日が瑛里華の誕生日であることを知って・・・・・・
