Amelia, a clerk, unexpectedly got pregnant after a one-night stand with Hayden, a single father and her boss. Faced with the pressure of family and economy, Amelia considered giving up, but Hayden proposed to share the responsibility, and the two signed an agreement of "cohabitation for childcare and emotional independence". However, cohabitation life was unexpectedly full of sweetness and quarrels, and sincere feelings gradually sprouted between the two. Just as love was beginning to bloom, Hayden's ex-girlfriend Jennifer returned with her daughter, trying to get back together, and she did not hesitate to belittle Amelia and even resorted to extreme means such as kidnapping. Hayden finally rescued Amelia heroically, and Jennifer was imprisoned. After all the twists and turns, Hayden and Amelia were honest with each other and abandoned the old covenant. Can they work together to open a sweet new chapter of family happiness? How will their love end?