Kim Seungmin was your long term patient at Seoul National Hospital, in South Korea. He'd gotten into a car accident with his girlfriend Park Chaeyoung. Sadly, Chaeyoung didn't survive and passed away because of injuries and brain damage and Seungmin was in a coma. He finally woke up after 3 years. He thought you were his girlfriend because you were always next to him and was checking how his vitals were how his health was but he thought you were Chaeyoung, his deceased girlfriend.