The protagonist is an "inheriter of intangible cultural heritage" that no one looks down upon - an ancestral craftsman who makes paper figurines, cuts window grilles, and performs shadow puppetry. After entering the ghost story, he discovered that the "rules" in the ghost story are essentially a system of ancient folk taboos. Paper figures can stand in for death, window grilles can seal doors, and shadow puppets can attract souls—these intangible cultural heritage techniques that have been forgotten by modern people are precisely the "underlying codes" for cracking ghost stories.
