Dan Dan lives with her stepbrother, Dae Bum, the ever-failing businessman, and her stepmom. Tired of putting up with them, she leaves home. Feeling down on her luck, she climbs up a mountain. There, Dan Dan runs into Young Guk, who is hiking while dressed in a suit. Young Guk is the capable chairman of a corporation, as well as a widower with three kids. By chance, Dan Dan becomes a live-in tutor at Young Guk's house. As they start to live together and look after Young Guk's kids, they find themselves in situations of conflict, both small and large. Despite their 14-year age difference, they start to grow fond of one another. With the help of Dan Dan, will Young Guk be able to overcome his grief and grow closer to his kids?