Minami Sakuta (Moka Kamishiraishi) is a 2nd grade high school student. She loves to swim and is a member of the swimming club. Minami Sakuta also enjoys anime and, in particular, "Maho Sakan Otome Buffalo-Koteko." She meets Shohei Moji (Kanata Hosoda), who is drawing "Maho Sakan Otome Buffalo-Koteko" on the rooftop of their school. Shohei Moji is also in the 2nd grade of high school and he is a member of the school's calligraphy club. One day during their summer vacation, Minami Sakuta unexpectedly starts a journey to find her missing father. Shohei Moji joins her along the way. During their journey, they meet various people and undergo personal growth.