The keyitu (THE K2) 'Yoona OST theme song for the second yuseongeun [rarely]'Rarely' it is a minimalist piano-based ballad, the song containing the lyrics bittersweet and sad hearts of the protagonists of the drama, understated melodies and compelling. In particular, mainly it inserted into the theme song of the heroine and Anna (imyunah minutes) and can increase the audience of the commitment. In addition, the delicate and expressed through the voice of the more compelling yuseongeun ahryeon wait for a mixed fate and love will be gone stimulate the feelings of the public. 'Rarely' There was a guitarist playing guitar on the album baksinwon participate hamkkehan tasks such as B1A4, Kim Pictures, lyricist, composer, arranger raised the completeness of the songs take the team JYP Publishing Department produced 'kkuldanji.As well, oil is also a talented artist with experience participating in various drama OST tasks such as tvN drama 'The second twenty years', 'My Secret Hotel', 'huahyu', a luxury OST to sad emotional and soulful a voice of yuseongeun It was born.