'안녕, 나의 첫사랑, 꼭 다시 만날 테니까' Keum Donghyun - CEO of a dancing company in Korea. He has a wife and 3 children. But he divorces his wife and marries his girlfriend. Has no idea that he has another child when he divorced Yebin. Kim Yebin - wife of the famous dance company's CEO, Keum Donghyun. She also worked as his personal assistant and driver. They had 3 children before they divorced because she caught him cheating while carrying their child. What will happen? Yebin wants to give up the baby but falls ill while being pregnant and the baby helped heal her after she was born. How will Donghyun react to his last child? Will they get back together? Or will someone leave to the stars?