I've watched lots of childhood friends become lovers dramas, but this drama impressed me because they bicker a lot and it's entertaining. 

It tells about Bae Seok Ryu, who was working in the US, coming back secretly to Korea to tell her family that she quit her job and canceled her marriage. From the first 4 episodes, I could tell that she has been hard on herself and has experienced terrible stuff in both work and relationships. It was Choi Seung Hyo, a childhood friend, who gave her the motivation she needed to start over in Korea. We will discover who has been in love with whom longest and since when in the meantime, along with those fleeting moments of spark that have occurred since they were young.