Yoon Ye Eun has been married for 7 years. She is a housewife and works hard taking care of the family on her husband, Lee Jin Sup's side. Her in-laws though give her a hard time, but she is positive and happy. Her husband's business is doing well and they move into a new house. However, she then finds out her husband is having an affair. Yoon Sang Eun is single and runs a small piano institute. While running her piano institute, she has fallen into debt. She meets Choi Jae Woong through a matchmaking agency. Choi Jae Woong proposes to enter into a contract marriage with Yoon Sang Eun and in return he will pay off her debts.

Happy Sisters ran for 1 season. No new episodes are scheduled.