To save her sister's life, Xu Yanqing sells her virginity to a stranger named Yu Zhi. A year later, at a gathering with friends of her suitor, Song Jin, she encounters Yu Zhi again. Recognizing her, Yu Zhi forces her against a wall, causing Xu Yanqing to flee in panic. Back in the private room, Song Jin confronts her, revealing that only Yu Zhi possesses the medicine needed to cure her sister. Desperate, Xu Yanqing pleads for the medication, but Yu Zhi obstinately complicates matters, determined to drag her back into the chaos of that fateful night.