Chu Yao, the foremost immortal of the righteous path, is aloof and desireless, the moonlight of the cultivation world. Her only stain is her rebellious disciple, Xie Yuan, who betrayed his master and fell into the demonic path, becoming the Demon Venerable. Just as she enters seclusion to break through to ascension, a great tribulation of inner demons descends, taking on Xie Yuan's appearance to unsettle her Daoist heart. Chu Yao cuts it down with a single strike, but the inner demon doesn't dissipate. Instead, it gathers into the form of a three-year-old child, who clings to her leg and calls her “Mommy,” then points at the demonic energy in the sky and calls it “Daddy.” The child wields both immortal and demonic powers. One cry and the spiritual plants on the immortal mountains wither; one laugh and blood lotuses bloom in the demon realm. Worse still, the child says he was born of his parents' “spiritual union”! To keep this “walking weapon of causal law” under control, Chu Yao has no choice but to descend the mountain and find her old rival, now the supreme ruler of the demon realm. “Xie Yuan, our inner demon has become a real child. Are you going to do something about it?”
