Indeed.
Back then, Hou Dongbai had told them that because they had killed the Wolf King, the Level 5 Demon Emperor had wanted to cross the barrier between the humans and the demon beasts to avenge its descendants. Fortunately, it was stopped by Xuan Yang the Perfected Lord.
Now.
Although that Level 5 Demon Emperor could not enter the human territory personally, it didn't mean its other descendants or subordinates wouldn't be lingering around and spying on their every move.
Once they were found in the controlled area of the demon beasts, those Level 4 demon kings would definitely not mind taking their heads to the Level 5 Demon Emperor to receive rewards.
At that time, it was hard to say what would happen.
Apart from this,
The Shangguan family and the demonic cultivators of the Zheng Nation had a lot of grudges against them.
It was hard to guarantee that they would not take this opportunity to do something harmful.
So.
