She is a plastic surgeon. He is a gangster. She is always cheerful, and he is grim. But still, a strong feeling flares up between them. Many years ago, Kan-jae sheltered his future boss, and the guy became loyal to him. But living in the boss's house was not easy at all. The boss has a son, Se-yeon, about the same age, and he was jealous of Kan's closeness to his father. Mi-ju supports her family on her own, including her pregnant sister and her father, who is a priest. Although she is a plastic surgeon, she did not choose this profession for money. She barely has enough to pay the rent. It turns out that Mi-ju lives next door to Kan-jae's girlfriend.