Blue wind blows

Ao, a 12-year-old boy, lives with his mother and little sister on Sado Island, in Japan. He misses his father, who has gone missing without a trace. While his mother tries to deal with the loss in her own way, Ao and his sister run across the island and scream at the ocean. In the mysterious transfer student Sayoko, who inconspicuously swipes books from a school library, Ao finds a confidant, and together, they feel less alone.