Long ago, a terrible war split Earth and Sky, forever dividing the two worlds. The inhabitants of Earth, with their brief lives, began to remember Sky only in myths and legends, while the immortal sky‑dwellers simply paid no attention to the Lower world—after all, there was no Akuto, the magical energy that granted them strength and longevity. And then disaster struck—Akuto began to rapidly deplete, and the erupting wars only accelerated the crisis. While elf‑like residents of the Upper world fought over the remaining magical power, Munto, the mightiest of the Celestial Lords, learned from the seer Rueri that the key to saving both worlds must be sought on Earth… Thirteen‑year‑old Yumei Hidaka loved rainy days, because then she saw the sky just like other people, without the majestic islands floating in the blue expanse. But lately her visions have become unsettling and frightening, with huge cliffs and stone columns collapsing from the heavens. Yumei understood why her homeland Japan had been plagued by tsunamis, earthquakes and other cataclysms, but she feared sharing these thoughts even with her best friends Itiko and Suzume until an unknown man in red appeared before her in a fiery glow…