[Machine Translation] Frontier, whose boogeyman's technology has enabled him to travel to a parallel world through a four-dimensional door, decides to follow the boogeyman to rescue his missing students. However, the parallel world that Frontier arrives at through the 4-dimensional door is a world ruled by insect-evolved insectoids. Frontier fights the Boogeyman, who ambushes them, but in order to locate the students, they are caught on purpose and subjected to severe torture, where a startling revelation is made! The boogeyman's boss, Medusa, who was supposed to have defeated him, was a shadow of his former self, and the real Medusa was a human trafficker who was supplying food to the insectoids. After discovering the student's safety, Frontier finally hunts down Medusa, but the insectoid Daniel stands in his way. Daniel parasitizes Frontier with countless ticks and manipulates its motor center at will, driving Frontier to the brink of self-mutilation. Will Frontier be able to get its students back?