Liu Shuang, princess of the Nine-Tailed Fox clan, destroys her Spirit-Locking Bracelet and falls into the human world to escape an arranged marriage. There, she unexpectedly encounters Xue Yu, a retired soldier king in female form. A resonance between their blood pacts forces the two into an entanglement. Liu Shuang's yandere nature gradually emerges: she binds Xue Yu with a marriage thread and warns off other women with fox incantations. Meanwhile, Xue Yu's split personality, the coldhearted soldier king in his male form and the sweets-loving girl in his female form, is gradually torn apart through her interactions with Liu Shuang. Their relationship begins with mutual exploitation, but they slowly become caught in a whirlwind of love that crosses the boundary between demons and humans.
