izumu
I bet on the "second" timeline, (first one being the one where the blood demon destroys the world), the mc becomes the calamity the proper way and destroys everyone except the heavenly demon(since she is not of the world). And he definitely regreted it and I bet the heavenly demon is just trying to carry out his wish to not destroy the world.
All just guesses though.
Lol, the heavenly demon was implied to one of the strongest beings in existence. Much less the gu clan. As in stronger than the mother.
She said implies it one of the chapters before MC died.
This god dang novel and it's thousand mysteries..
It's going to take years to complete.....
I hope everything goes well.