Yoona has been comatose for more than 3 years and when she woke up everything has change including the love of her long time girlfriend name jessica jung .Since she woke up yoona feel the cold attitude of jessica giving to her.   

    Unrequited love or one-sided love is love that is not openly reciprocated or understood as such by the beloved. The beloved may not be aware of the admirer's deep and strong romanticaffection or consciously reject it.    

Im yoona is a guardian angel of kwon yuri. Her duty is to protect yuri from harm and always by her side. Its her responsibility.. An guardian angel should do.. But what if she fall inlove wiht a human ?? Not just a human . but a human that kwon yuri love... What will she do if she's the one who will harm's yuri's heart? Will she choose the one she love or she will stay as a guardian angel.