Lee Kang-joo is a ceramics technologist and single mother. Her ex-boyfriend Yoo Ho-nam hadn't known that she was pregnant when he left her to study abroad. Now a psychologist, he returns to Korea, but Kang-joo hides the fact that he's the father of her daughter, Byul. Meanwhile, Choi Seung-hyun is a fitness club owner and the son of Kang-joo's mentor and boss. He has loved Kang-joo since high school, but not wanting to lose their friendship, she's remained unresponsive to his romantic overtures.
^"MBC <잘했군 잘했어> 커플들이 사는 세상" [MBC's Good Job, Good Job: Couples in the Real World]. TenAsia (in Korean). March 17, 2009. Archived from the original on December 22, 2015. Retrieved June 10, 2015.
^"Cheer Up on Love". MBC Global Media. Archived from the original on March 9, 2015. Retrieved June 10, 2015.