After their disastrous encounter with the bizarro Demon King Ziggy, Shiki and his friends set out on a journey into outer space, beyond the Sakura Cosmos. Their first stop is in the Aoi Cosmos, on a planet largely covered in water. Under the vast ocean, they find a temple housing a critical clue to finding the matriarch of the cosmos, Mother! But in order to obtain the clue, Shiki must overcome a fiery obstacle that requires enlisting the tearful aid of an unexpected ally.