Hairi Takahara, a city boy escaping a difficult home life, arrives on the rural island of Torishirojima in the Seto Inland Sea to sort through his late grandmother's belongings. Over the course of summer, he meets four girls at the center of the island's quiet world. Shiroha Naruse has forgotten her summer vacation; Ao Sorakado chases local legends; Kamome Kushima searches for a pirate ship; and Tsumugi Wenders is trying to find where she belongs. What begins as a temporary stay stretches into a season that reshapes Hairi's sense of home.