Everything she said was true.
Bai Mengjin's Golden Core cultivation was indeed drawn from Bai Chong'an. Before the demonic qi in Ling Bufei's meridians was purged by the heavenly thunder, she had also relied on her cultivation technique to draw away the demonic qi and ease his agonizing attacks.
To trace it back even further, the Night Demon had indeed been devoured by her, causing him to lose points and finish second in the Spiritual Cultivation Grand Assembly.
Chapter 290