Yuki is a 19-year-old Japanese nurse trainee who has always dreamed of building a successful career in medicine. After working hard to prove herself, she receives a rare opportunity at Minseo Medical Center, one of Seoul’s most prestigious hospitals. She is offered a well-paying position as a personal assistant to the hospital’s CEO while also being given the chance to train under one of the most respected surgeons in South Korea.

What Yuki does not expect is that the CEO and surgeon she will be working alongside is Min Lee—the person who shaped the most important years of her childhood.

Min and Yuki first met when they were young children and became inseparable best friends. As they grew older, their friendship slowly turned into their first love. They dated throughout their teenage years, sharing years of memories, laughter, and dreams for the future. However, their relationship eventually ended when Min broke up with Yuki, leaving both of them with unresolved emotions and unanswered questions. After their breakup, they went their separate ways and lost contact.