Real life and growing up are bearing down fast upon the residents of the Hidamari apartments, but they're going to make time for one last summer together, full of fun in the sun! Amidst Yuno deciding on the topic of her self-assigned summer project and Sae and Hiro attending summer sessions to help focus their goals for life after high school, the girls will really have to go all out to make sure it's a summer they'll never forget!