I became my ex-boyfriend's guardian.

Jiyoon and Sehun, who have been dating for ten years since their first year of high school, had a massive fight beyond imagination and were both deeply hurt. However, perhaps because their seven years of memories were so happy, they later found it difficult to fall in love. Three years later, Jiyoon became a nurse. One day, the man she thought she would never see again visits as her patient... but he has lost all memories of her and everything they shared together.