Li Shenxing secretly admired Wen Chuchu in college but lost contact when he went abroad. Later, he learned his grandfather had arranged for her to be his fiancée and returned to China, only to see her with an older man. Misunderstanding her behavior, he grew conflicted. A year later, Li was drugged and, due to a scheme by Wen Chuchu’s sister Wen Beibei, ended up in a hotel room with Wen Chuchu. After an intimate encounter, Li mistakenly thought it was Beibei. He promised to take responsibility if she lost her purity for him. Li’s grandfather secretly had them registered as a couple. Over time, Li realized Wen Chuchu was not what he thought and uncovered Beibei’s deceit. In the end, Li and Wen Chuchu exposed Beibei’s schemes and built a happy life together, raising their daughter in harmony.