In her previous life, Xu Yunshu was betrayed by her sect and met a tragic end, dying with deep resentment. Reborn just before that tragedy, she awakens Mu Tinghan, an ancient sword spirit who has been dormant for ages. She thinks she has found a cold and powerful sword cultivator who will help him cultivate and take revenge. Little does she know that beneath her aloof exterior lies an obsession and possessiveness carved deep into her very soul. Their souls are bound by a shared pact: when one prospers, both prosper; when one suffers, both suffer. Whenever someone else comes even a step closer to him, murderous intent surges within her. Inside his sea of consciousness, she relentlessly closes in, wanting him to belong entirely and exclusively to her. On one side lies a blood feud that must be settled; on the other, a dangerously obsessive sword spirit from whom there is no escape.