She loved him when they were in Jiang Guo, but he pretended not to know because he was his adopted brother. In the end, she and her love disappeared into the world.
He suddenly repented, what did the world and all the people have to do with himself? So he made a contract with the Demon Lord, exchanging his own skin for a life and memory that will remain unchanged for thousands of years. Just waiting for her reincarnation.
Thousands of years of waiting have already made up for the mistake of that year, and that leap of thousands of years ago has already made him fall in love. But I don't want to live long and have no way to save myself. The fate of a thousand years ended a thousand years ago, and now it is just obsession. Who is right and wrong in joys and sorrows? Why not let my memory stay in the last night of loving you in this life.