Yoo Eun-ho (Son Ye-jin) and Lee Dong-jin (Kam Woo-sung) meet one day at the bookstore where he works and they are immediately drawn to each other. They fall in love after subsequent meetings, and are eventually married. Two years later, they are divorced.
Dong-jin still works at the bookstore, while Eun-ho works at a fitness club. Even so, a year and a half after their divorce, the two still meet in their favorite bakery for breakfasts, quarrel over trivial things like a married couple, and eat dinner on their wedding anniversary with a free meal coupon provided by the hotel where they got married. The narrative is punctuated by either character's internal monologue on their past and current relationships, as new love interests enter their lives.
All of this makes them wonder whether these lingering feelings are love, although both are too afraid to start over, and even more afraid to end the relationship completely. With neither brave enough to confront each other about the misunderstanding on the day Eun-ho had a stillborn baby, they are unable to move on.