In Tatsumi Town, mysterious disappearances are occurring one after the other. Kiriya gets a vision of a lovely mystery girl with pointed ears. A book advocating for a different world is discovered. And Mao, in quest of her long-lost companion Zero, arrives in our planet. But she didn't expect to find Souma and Kureha, much alone accidently transport them to her realm. Souma and Kureha must now find a means to return. However, other forces are at work in the darkness, and Souma and Kureha will discover that returning is more difficult than they thought.