A middle school teacher quits her job to come to Beijing as she is about to marry her fiancee. In order to make some money, she becomes a tutor for the bookseller's daughter.

Ma Lie Wen sells books for a living. Out of a strong sense of responsibility, he chooses to continue taking care of his ex-wife Wang Yi Ru who suffers from bipolar disorder. The arrival of family tutor Jian Dan brings him a touch of comfort. Jian Dan was originally a middle school teacher. She quit teaching in order to marry her fiancee Feng Chun Sheng only to be betrayed by him.

Ma Li Wen advises Jian Dan not to compromise when it comes to marriage. The two go on to develop inexplicable feelings for each other, yet they never cross the line due to Ma Lie Wen's complicated situation. At this time, Ma Lie Wen's ex-wife fully recovers and wants to get back together again. Ma Lie Wen is faced with tough choices between responsibility, love and a precarious career.