People are gathered by recruitment or being kidnapped.These people take part in the Werewolf Game. The participants must risk their lives in the game, while wealthy people wager on the winners and losers of the game. Masamune (Yuuki Ogoe) works as an operator of the game. He finds out that female high school student Yuzuki Natsume is one of the participants in the Werewolf Game. Masamune once taught Yuzuki Natsume as a private tutor. He wants to save her and he is willing to risk his life to do so.