Description of characters:

Yoona, was an outstanding student and aced her subjects. When she saw Taecyeon extorting money from a student, she stepped in and that's how they met. Initially, Yoona hated Taecyeon for disrupting her lessons but found herself amused by him and ended being friends.

Taecyeon, was a rowdy and family rather messed up. A mother who gamebles, father died when Taecyeon was at a young age, he was left with his mother and the riches his father left for him. He extorted money from people until he was caught by Yoona one day. He fell in love with her. 

Junho and Yuri- Friends of Taecyeon and Yoona respectively. Started dating before Taecyeon and Yoona did. 

The two wanted to be more than friends. But when they did, Yoona received a scholarship to study at England to be a doctor. Unable to break the news to Taecyeon, Yuri found out and lied to Yoona that he had another girl outside to make their seperation easier. Taecyeon unaware of any of this, received a message from Yoona saying that she was leaving to England. Unable to catch her, he continued his studies too. 10 years later, Taecyeon's mother was involved in an accident and Yoona was her doctor. Taecyeon who was overseas came back and found his mother. Taecyeon applied a job as a nurse(he studied nursing after Yoona left in hope of seeing her again as a nurse and doctor relationship). He found Yoona the day when he was waiting for the doctor to finish his mother's check up. However, Taecyeon did not come back alone. He came back with a girl from another country, Sarah. Sarah liked Taecyeon although Taecyeon only treated her as a sister. When Taecyeon's mother died, he cried to Yoona afterwhich they became friends again. One day, Yoona did not save the person in an operation theatre. She felt guilty and Taecyeon went to her house(he lived beside her) and comforted her where the two of them finally did what they wanted to do 10years ago, make love. Yoona wanted to leave for good. Will they continue to be together or will they be torn apart again?