Seo Yoon-joo: Actress Jung Yu-mi

She is a veterinarian and daughter of a CEO of a medium-sized business. Due to the hysterical personality of her stepmother, Yoon-joo learned to tread lightly around her, since she was little. After learning about her biological mother, she tracks down her and rents a room at a boarding house she runs. There she has trouble getting along with Cha Ki-jun but falls in love with him, never knowing the bad history between their parents…

Cha Ki-jun: Actor Choi Tae-joon

As the second son of the owner of a conglomerate he has been doted on by his parents. Despite opposition from his parents who wants him to study business, Ki-jun decides to be a chef and rents a cheap room at a boarding house. There he meets Yoon-joo and wants to marry her but his parents force him to choose between marrying her and becoming a chef.

Kim Soo-jin: Actress Uhm Hyun-kyung

Yoon-joo’s half-sister who is rebellious and hates being poor. With a slim figure and pretty face, she becomes a model but has a hard time making it into show business. So she pursues Cha Sung-jun, the scion of a conglomerate, and tries to become his wife through any means possible.

Actor Koh Sae-won

He is older brother of Ki-jun, cold and calculating. While he has a calm demeanor and appears to be logical, he is very cruel and has no empathy for others. He reluctantly marries Soo-jin as she lies to him she has got pregnant, but when he learns the truth he breaks up their marriage. When his younger brother brings home Yoon-joo to introduce her as his love interest, he is astonished to see her because she was a girl he once met on an arranged date, which creates an awkward tension between the brothers.