"When you kill an enemy, a person from this world dies." Confronted with the truth of the battle as a "Barrier Master," Arata Meino struggles, but upon learning the reason for her partner Yosu's past and fight, they resolve to bear the sins together. In the midst of a fleeting peaceful time, while gradually accumulating what is precious, Meino continues to face the intensifying battles against the "Beasts"—