Siblings Sora and Shiro are now kings of Elkia. But instead of taking care of state affairs, they prefer to read books and gamble. Steph, who therefore has to take care of everything, finally loses her patience and challenges the two to a game. After losing again and again and having to do everything Sora and Shiro ask of her, she is soon dressed like a half-naked girl with animal ears. When the siblings learn that this is what the Werebeasts look like, they immediately want to conquer the realm of the sexy "Kemomimi girls". But without knowledge of this realm, they can't get started, because Elkia's library is occupied by a powerful being, a grand piano. "Blank" has to throw himself into an all-important game against the wing called Jibril. The game: "Materialization Letter Chain". In this case, something that does not exist is materialized and something that exists disappears. Can Sora and Shiro defeat the overpowering wing?