Seventeen-year-old Nao from Tokyo faces her world shattered by tragedy, her family lost in an accident that forces the court to place her in protective custody. Doctor Chieko Nishikawa of Okinawa opens her home and heart, offering the foster girl a second chance at family. Yet Nao struggles to trust anyone in her quiet new town—until Van arrives, breaking through her carefully built walls without either of them expecting it. A devastating accident during vacation sends Nao into an inexplicable ten-year sleep. When she awakens, horror floods through her: she's trapped in an unfamiliar body, ten years older in a world she no longer recognizes. The girl whose body she now inhabits remains a complete mystery. Desperate to reclaim her original self, Nao must navigate this bewildering existence while uncovering the dark truth behind her impossible transformation.