Tired of endless slaughter, Lu Qing'an, the Eternal Night Demon Emperor, retires to the Immortal Ruins and marries Xu Qingying, living with her for a thousand years. To attain the rank of the Immaculate Emperor, his wife publicly divorces him and takes half of his cultivation. Heartbroken, Lu Qing'an returns to the Demon Realm with his two daughters and no longer hides his true strength. With a system that returns cultivation a millionfold, his power surges. He finds cultivation techniques for his daughters, ventures into the Heavenly Fallen Demon Cavern to obtain divine metal, and arranges for them to train at the Demon Willow Academy. Meanwhile, his former sister-in-law, Xu Yunyi, chooses to remain in the Demon Realm to pursue the Dao of Formations, while old friends such as Consort Xue Tianfei gather around him. Far away in the Immortal Ruins, his former wife and son embark on a different path.