Kokone Morikawa suffers from a sleep disorder that blurs the line between her waking life and her dreams. In reality she is studying for university entrance tests, yet in her visions she becomes the princess of Heartland—a future where artificial intelligence is outlawed.
In this realm, Kokone learns more about her family's history and a truth that her mechanic father has been shielding her from. The boundary between the two realms with passing night, forcing her to confront both the memories of her ancestors and the looming threats that seek to exploit her knowledge. As the two worlds collide, she must guard this secret against malevolent forces that are both dream‑like and real.
