While exploring an ancient shrine, Nanami stumbles upon a glowing mask hidden in the shadows. The moment she touches it, she feels an immense power surge through her body. This is no ordinary mask—it is the legendary Moon Mask, said to control the heavens themselves. As Nanami puts it on, the full moon rises, and the mask’s power begins to awaken, affecting the wind and shadows around her. Now burdened with the responsibility of being the mask’s keeper, Nanami must learn to control its immense magic while protecting her village from the dark forces that covet its power.