Xu Wanruo, the illegitimate daughter of a merchant family, seeks refuge at the Xie residence in the capital. The top scholar and powerful official Xie Xianyu secretly keeps her as his mistress. Remembering her mother's dying wish never to become a concubine, she pretends to please him while secretly plotting her escape again and again. By day, they maintain a careful distance; by night, they engage in an intimate game of push and pull. Xu Wanruo originally intended to seize an opportunity to escape and disappear far away. However, she never expected that Xie Xianyu, who appears gentle and courteous on the outside, is actually obsessive and dangerously possessive, determined to keep her by his side. Xu Wanruo carefully maneuvers around him, pretending to appease him, but refuses to become a caged songbird. Later, she fakes her death and leaves the capital. After enduring countless hardships, she becomes a compassionate physician appointed by imperial decree. Meanwhile, Xie Xianyu is willing to break with his entire clan and voluntarily renounce his family name, all for the sake of marrying her as his lawful wife.