The Ninetieth Day of Accidental Discovery

What is the real song of everlasting regret? Everyone's first love is a regret. It changes with time. It may only last for a moment. It may be as long as the Song Dynasty before the 21st century, or even as long as the 21st century to five thousand years in the future. The distance between me and my first love is only the distance from this shore to the other shore. My name is Su Xingge. My favorite is "Song of Everlasting Regret" by Tang Dynasty poet Bai Juyi. This story also begins with the Song of Everlasting Regret and will never end.