I don't know.
No one knows.
Demons, terrifying because of this.
No one knows when the person next to them is replaced by a demon.
No one knows when the person next to them will suddenly become a demon.
One second they're a brother, a relative, a lover; the next, they're an enemy in a life-and-death struggle.
The scariest part is if you guess wrong.
Then what they kill isn't a demon, but the most important person to them.
That kind of guilt, the pain, is often unbearable for ordinary people.
That's why many of the Foolish Underworld's people are actually mentally unstable.
Not many can have such strong spirits.
Like at the scene, the friends and family of Shi Chengxin are alright, they just watched Shi Chengxin transform from a person into a demon and then die tragically.
But the one who's really tormented is Li Baizhen.
He's under immense pressure.
From decapitation to destroying the corpse, to the corpse transforming and the demon appearing.