Tashi, the demon hunter, finds himself embroiled in a mission to track down a mysterious and deadly creature. This creature, known as an Yokal oni, special yokal well known as Kagekotsu is not just a mindless monsters but is being controlled by a hidden parasite. The parasite's ability to blend into society makes it extremely difficult to detect. The urgency of the situation is heightened by the Hyuga Hyottoko Mask Summer Festival in Tokyo, where Tashi has only less than 13 hours to locate and eliminate this threat. Meanwhile, the backdrop of numerous disappearances of missing people and animals across Japan adds to the tension and mystery of the story.