Lin Mo, a debt-ridden young man, received a strange phone call and entered an abandoned hospital in search of his missing sister. However, he was attacked by the ghost of a child in red. On the verge of death, he activated the mysterious system "Spirit Book". The system digitizes supernatural power, issues tasks, exchanges skills, and opens ghost illustrations, giving him the capital to fight against ghosts. However, as the investigation deepened, Lin Mo discovered that his sister's disappearance was connected to a series of supernatural kidnapping cases. There were items from his childhood left at each crime scene, and the murmurs of the twelve children in red in the dream pointed directly to his forgotten past.
The "Spirit Book" system revealed that Lin Mo was the key sacrifice in the resurrection ceremony of the ancient evil god "Shadow of the Old Day" - the thirteenth child in red. Within seven days, he must use the power given by the system to fight against five powerful BOSSs controlled by the "Kirikakukai" (representing the five nodes of the ritual: memory, fear, blood, time, and space), solve the mystery, and save his sister. But every time he uses the power of the system to solve an incident, it will accelerate the recovery of his memory and push him to the abyss of final sacrifice. He wanders between the official paranormal investigation bureau, hostile players, and wavering insiders, counterattacking in despair, turning terror into a controllable target. In the end, he faced the ultimate choice: Should he sacrifice himself to complete the ritual in exchange for his sister's survival, or should he find a third way to completely destroy the "Shadow of the Past" and the systemic conspiracy behind it? This is a race against time, fate, and one's own fear.
