The Promise Sealed with Our Lips - Volume 2 Chapter 4

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.

After 2000 years has passed, the ruthless demon lord has just been reincarnated! But his aptitude at an academy for nurturing candidates for demon lords is, “Inept”!?

Our straight (?) bottom woke up ten years into the future and found himself on the bed of his childhood friend… At the start, the bottom was shocked to his very bones, but he soon quickly accepted this premise and found the whole situation to be rather amusing. Precisely then, the bottom once again went back to his timeline — back to when he and the top were just platonic childhood friends.

Lu Jiangxian died after staying up late one night. Yet, he finds his soul trapped in a fractured, bluish-gray bronze mirror. He falls into a boundless world of immortal cultivation and finds himself in the perilous landscape of Mount Dali. There, a small family from a small village by Meiche River picked the mirror up and is bestowed with the ancient teachings of the immortal ways, heralding the dawn of a splendid new era.