Ji-woo's want is to become a violinist and perform with popular pianist Jae-yeong. Ji-woo's dream is a man in her dream who helps Ji-woo in the past and tells her to find him. One day, a mysterious being who calls himself a "Mong-sin" appears in front of Ji-woo. Mong-sin suggests a dream deal, saying, "If I sell a dream featuring a man, I will make Jiwoo's dream come true.".