The story follows a human named Kris who lives in a world inhabited by monsters. Kris and a classmate named Susie fall into an unknown place called the "Dark World" where they meet Ralsei, who informs them that they are heroes destined to save the world. The trio meets various beings who call themselves "Darkners" during a prophesied quest to seal the duplicate Dark Fountain. Mainly through the combat system, the player navigates through different kinds of bullet hell attacks by enemies, which can be resolved peacefully or through violence.