Ai Qing, a new employee who encountered a rental fraud, unexpectedly shared a house with Yan Chuan, a junior from the same school whom she had met once. The two gradually developed feelings for each other in their warm cohabitation life, but at this time, Ai Qing's first love returned to China, disrupting everything... First love Gao Jianze launched a fierce pursuit of Ai Qing, and Ai Qing also discovered that her cohabiting boyfriend Yan Chuan had a secret that could not be told. Yan Chuan was in great pain due to the deception, torment and guilt of his lover. How can this "love contract" get back on track?