In the near future of 2025, technology is beginning to emerge, but the world has become strange because of the "permanent Ghost Festival". The passage between Yin and Yang is open 365 days a year. Human beings live on the surface, the underworld occupies the underground pipe network system, and demons live in abandoned buildings. In order to modernize and reform, the underworld implements the "Underworld O2O" plan, while the Special Affairs Administration (STA) on earth is committed to maintaining stability.
The protagonist is a delivery boy who is bound to the forced order-taking system "Are You Hungry?" Negative reviews will deduct yang life, while positive reviews will reward yin virtues, which can be exchanged for superpowers. Special achievements such as completing 30 consecutive orders on time can unlock a 5-second pause in time, and appeasing a gluttonous ghost can grant you the ability to freely expand and contract your body.
Driven by the reformists of the underworld, Yan Xiaoluo, as the CEO of the underworld, his real purpose is to collect the energy of human fear. Chen Xuan of the STA Special Service Section regards the protagonist as the source of the imbalance of yin and yang, and carries a deformable mahogany gun to hunt down the protagonist. Daji from the Demon Entrepreneurship Gang used the inhaled yang energy to make milk tea ingredients and developed the "Yao Qi Forest" Internet celebrity drink.
As the story develops, the protagonist gradually discovers the truth about the navigation helmet - it is actually the soul of the first-generation delivery driver, and the system will gradually devour the user's memory. The protagonist must survive in the gap between the Yin and Yang worlds, uncover the truth of the system, and at the same time deal with the pursuit and conspiracies of all forces.
