But shortly after school begins, the twins uncover a dark, mysterious secret: Students have been known to walk off into the surrounding bushlands, where they have vanished completely, without a trace!

    One day, with Yoon Bum's obsession toward Sangwoo reaching its peak, Yoon Bum decides to enter Sangwoo's home. But what he sees inside is not the Sangwoo he had dreamed of. (Chapters 1-19)