The girls of 765 Production Studio are eagerly preparing for the International Music Festival on Vacation Island. Coupled with an amusement park and a high-class resort, the festival promises several days of fun for everyone. That is, until their producer announces that they only have enough room for one unit to participate. In three different scenarios where everyone is split into three groups, one of the three is chosen to partake in the International Music Festival, where they are treated to a three-day vacation before starring in the festival's concert. From the moment they step off the boat until the main event, each group of girls experiences the festival in their own way, excited to take part in the highly anticipated performance.

Mini episodes of Kotoura-san introducing each of the series' characters.

After earthquakes suddenly took place in the Kumamoto Prefecture, Natsuna Keyaki lost contact with her dearest online friend, Itsuki. With nothing but a drawn picture of the landscape, Natsuna embarks on a journey from Tokyo to Kumamoto to find her. When Natsuna gets lost in a rural area of the disaster-stricken prefecture, she encounters a policeman and an energetic middle school girl named Izumi Chiba. Izumi, along with her hospitable family members, offers Natsuna shelter and information to assist her in her quest. With these kind locals helping her on every step of the way, Natsuna moves closer to discover what happened to Itsuki.

Yakumo has trained and searched for 4 years, following Pai's mysterious disappearance. However, when he finally finds her, not all is well as her memory seems to be gone. They attempt to return her memory by going to the Holy Land, birthplace of the immortal race of Sanjiyans.