Some flowers wither quickly, some scenery fades easily, and some childhood sweethearts whose faces have aged quietly are separated due to a misunderstanding, but neither of them can forget each other. Will they be reunited when they meet again? Who will tell the sad love story in each other's ear after so many years. Are we all in love wrong, or are we not strong enough or honest enough? If we are reincarnated, will we see each other again? I don't know whether the light at the moment of sunset is like a red thread, tightly connecting the fate of the two. Can we go back to the way we were before? Can love that has been separated by a wall start again?