A young male scholar named Izumo explains to the protagonists that a snake demon called Orochidayu has created false Shikon Jewels to share with many demons. They discuss of about the origins of the fours souls that constructs the Shikon Jewel. When arriving to an abandoned town, an adolescent boy unravels that a group of demon captures his parents the night before. Orochidayu later shows up with the group of demons implanted with false Shikon Jewels, as the protagonists strive in trying to conquer them.