MTL - Indestructible Primordial Spirit - v20 Chapter 127 Divine Calamity

The king of assassins was reborn, mastering both alchemy and poison. Sitting inside the space, there was a ghost that loved crying.

When the human princess, Lareina is sent as a bride for a peace treaty between the demons and humans, she ends up in a political marriage with the second prince of demons, Prince Azrael. Lareina falls for his gentleness that sets him apart from the rest of the demons in her eyes but on the night of their wedding, he is deployed to the war.Years after his abrupt departure, Azrael has finally emerged victorious and returned. However, much to Lareina's dismay, he has brought back a beautiful demoness with him. At the receiving end of his hatred, a heartbroken Lareina tries to save their marriage until all her hopes are shattered. Determined to carve a way for herself, she decides to end the marriage but she is met with a new challenge when her seemingly uncaring husband suddenly refuses to let her go.

The world that nurtured the civilization which reached the pinnacle of magic was on the verge of destruction.
The last survivor transmigrated to the past, when the magic civilization started growing, as countless mages were still fumbling their ways through the thorny paths of magic knowledge.
He, who came from the end of the magic era, aim to reach the pinnacle of magic.

- Description from Novelupdates

She never dreamed that she would meet him in the bathroom and they...Five years ago, she betrayed him for some reason and chose someone else, which deeply hurt him and he swore to make her pay the price. After the reunion, he launched a fierce attack on her, while she tried to escape this emotional entanglement.However, the red line of fate seems to have already tightly connected the two. Through repeated interactions and confrontations, they gradually uncovered their past misunderstandings and got to know each other again. His deep affection for her remained, and she was gradually moved by his sincerity.