After the land of the ancient gods, the Eternal Night Demon City rose to prominence overnight in the Demon Cultivation Inner Sea. To expand its territory, it constantly attacked sects surrounding the Demon Cultivation Sea, including the Cloud Heaven Sect where Li Muwan belonged. During the battle to protect her sect, Li Muwan was poisoned and her life was in danger. Upon learning of this, Wang Lin took her back to the Demon Cultivation Inner Sea. Wang Lin, with his early-stage Nascent Soul cultivation, fought against three city lords, becoming famous throughout the Demon Cultivation Inner Sea. He brought back an antidote to save Li Muwan, only to discover that the crisis was not over, and a thousand-year-old conspiracy was surfacing. Ultimately, relying on their love and their first fusion with the body of an ancient god after reaching the Nascent Soul stage, they joined forces to destroy the Demon Lord.