This is a lot of information, it needs to be unraveled slowly.
Regarding the Yunxiang Race's side, the demon's behavior is indeed strange, yet reasonable.
Since it left a spiritual curse passed down through the bloodline, if demons do not have a concept of lifespan, or their lifespan is extremely long, then at least it had contact with the ancestors of the Yunxiang Race in ancient times.
If the Yunxiang Race didn't need to exist, they could have been exterminated in ancient times, why leave them behind?
One can only speculate, perhaps the demon just wanted to make them fall into dust, to satisfy its malicious delight. After all, before Bahamut appeared, that guy always acted with ease and a playful attitude.
A more serious speculation is that it has a reason why it cannot eliminate the Yunxiang Race, or it pursues something that cannot be achieved by killing them all, only by suppressing them to prevent their rise.
