Kawi, a 30-year-old young man who lives a poor life in a narrow rented room, works on subtitles every day, has no savings, no dreams, no inspiration, and most importantly, no significant other. He was one of those in his prime who had completely failed in his life, while Pearmai, who is his first love and one-sided love for over 10 years, has a happy life. She is about to marry Pisaeng, a classmate who is handsome and good-looking and was a member of the same faculty during their time in college.Kawi discovers that the musical crystal ball, an important gift he had intended to buy for Pearmai in his freshman year, has taken him back in time to his 18-year-old life, where he attempts to mend his relationship with Pearmai. With Pisaeng always hanging around, waiting to be a roadblock, everything turned upside down. Instead of being fulfilled with Pear, instead, he fell for Pisaeng.