A week long vacation turns tragic, as the plane that the Takansahi's were aboard suddenly crashes. All passengers are missing, and the girls' relatives think it's best to split the three sisters apart.
After a lively morning, Yuuta accidentally leaves his phone at home. Shuntarou takes the opportunity to talk to Miu, much to Yuuta's chagrin. While Sora leaves to find Yuuta, a neighbor visits the apartment.
The girls ask Yuuta for a favor: to return to their old house and pick up some important things. While there a rush of emotions, friends and memories collide with the girls, and Shuntarou gets a chance to speak to Hina.
Sora is having trouble juggling her school activities, studying, and housework. Kurumi has ended her LumaLuma 7 run, and with both of them seeking something to move them forward, can they trust each other to help?