Yun Xiyue, a carefree young woman from Qingyun Mountain, has always dreamed of exploring the martial world below. In the back hills, she meets Xie Linyuan, a black-clad youth burdened by a blood feud and cold as ice. A healing salve, a wooden hairpin, and a blue-green sword tassel bring two people who should never have met to fall quietly for each other amid flashing blades and clashing steel.
But just as they finally grow close, they discover that a blood feud separates their families. Yun Xiyue’s master was one of the accomplices who killed Xie Linyuan’s entire family. On one side is the debt of being raised; on the other, a love etched into the heart. On one side is an unavenged blood feud; on the other, a deep affection too precious to betray.
In that battle, he used a technique that would kill them both to slay his enemy, then “died” in her arms. Three years later, she receives a letter from him: he is still alive, but now teaches in a small Jiangnan town, unable to wield a blade ever again.
They spend their lives fulfilling a promise that can never have a perfect ending. Yet the sword tassel swaying in the wind and the words they shared beneath the moonlight have never been forsaken.
This is a story about regret. But it tells us that true love is never defeated by regret.