In the last summer vacation before graduating from high school, Yuta Togashi (played by Jun Fukuyama) and Rikka Kotori (played by Maaya Uchida) still live a quiet life, but their relationship seems to have no further signs. During this period, Rikka's sister Touka found a job in Italy, so she decided to move her family overseas. As a sister, Touka is worried about her sister Rikka, who has a serious problem with the second-year syndrome and even has problems going to college. Yuta is full of anxiety when he learns that he has to separate from Rikka. Nibutani (played by Chinatsu Akasaki), who is worried about the two, comes up with a bad idea, so the boy and girl embark on an elopement trip all over Japan...