The world has been overrun by demonic beasts, and humanity struggles just to survive. Years later, the Spring of Life loses its divine power, the Tree of Life withers, and humanity loses the ability to reproduce. At this rate, the last human will die out in a hundred years. Lin Luo, a demonic beast hunter who spends his days hanging around taverns, suddenly receives an invitation from an old acquaintance: escort a little girl to the Spring of Life as a sacrifice, so that humanity can regain its vitality and fight back against the beasts. Lin Luo is torn with anguish, but his old acquaintance offers him a condition he cannot refuse. Lin Luo decides to return to the Spring of Life and fulfill the world's final mission.
