Du Fei, a young man from the lower levels of the Green Zone, accidentally awakens the Ghost Devouring System while trying to save his younger sister, who suffers from Spirit Energy Syndrome. By sacrificing his lifespan, he can devour supernatural entities and seize their special abilities. From terrifying subway encounters to the Esper Tournament, he devours spirits and grows stronger, only to become entangled in the power struggles of the Red Zone. Along the way, he uncovers shocking secrets surrounding his missing parents and the origins of the Seven Deadly Sins. Determined to uncover the truth and rescue his family, Du Fei and his teammates venture into the Dead Zone, facing S-rank supernatural entities and ancient Demon God Pillars. Torn between his humanity and his instinct to devour, he embarks on a perilous path that will pit him against the entire world.