In a world where swords and demons clash, Hana is a samurai who has lost all reason to live. One day, in the heat of battle, he comes face to face with a god—Amanogawa Josui, a vessel-god who can control water. With no other purpose in sight, Hana forms a pact with the deity, who seeks to return to the capital of heaven, and embarks on a journey that will change his fate forever...