A few brief annotations resolved a minor confusion in Tao Qian's mind.
It turns out the source of the Daoist lineage of the "Cannibal Scripture" is this pig-headed human-bodied Acquired Demon God. Demons like Pig Devil and Pig Demon find it most swift and convenient to cultivate this Great Lifebook Scripture.
While contemplating, he continued reading the final annotation:
"Tianpeng True Monarch's cultivation was careless, causing such a mistake, and the evil power created by his demon body mostly falls on the True Monarch. Such karmic cost is unbearable even for this divine spirit."
"Having fallen into Daoist Transformation and gradually weakening, he must also guard against the demon body seeking out the main body to devour it. Fortunately, the True Monarch has deep ties with the Daoist sects, and several powerful Tribulation Immortals protect him over the years, keeping him safe."
