As Kurumi Tokisaki ventures into an unknown world, she becomes entranced by a unique white feline. Unfortunately, their encounter is brief. Soon after, she meets Hibiki Higoromo, a semi-spirit with snowy locks, who reveals they are both contenders in a perilous competition among quasi-spirits. These entities engage in battles in the Neighboring World, with the victor being granted their heart's desire. Understanding the competition's regulations, Kurumi and Hibiki join forces and put aside their discord, forming an alliance.