Meet Jeong Yein she's an 17 year old girl who had a amnesia because of an accident when she was 7 years old. She lived with her auntie now because her own father abandoned her. Until she meets Jungkook, her long lost bestfriend. He thought she can remember him, but he was wrong. Jungkook helped her to bring back her memories and so on. One day he realized he started falling in love with his bestfriend Yein.