The first part of a two-part movie is a recap of a TV series called "Beyond the Boundary." In this story, Mirai Kuriyama is the last member of her clan of Spirit World warriors who can use their blood as weapons to fight against youmu, which are said to be manifestations of negative human emotions. One day, while thinking deeply on a school roof, Mirai encounters Akihito Kanbara, a rare half-breed of youmu in human form. In a moment of panic, she stabs him with her blood saber only to discover that he is an immortal being. Despite this revelation, the two develop an unlikely friendship as Mirai continues to try and kill Akihito in order to boost her own confidence as a Spirit World warrior. Eventually, Akihito convinces her to join the Literary Club, which also houses Hiroomi and Mitsuki Nase, two other powerful Spirit World warriors. As their bond grows stronger, so does the presence of youmu around them. The release of Beyond the Boundary, the most powerful youmu, is imminent, leading to a fight for survival.