"Oppa... mianhae... cheongmal mianhae"

Kyuhyun and ______ are siblings... they are very close to each other... but Kyuhyun left _____ to be a trainee at SME... _____ becomes very sad and felt that she is left behind... that's when she met Onew... they became best of friends.... until ____ decided to go to Japan to study... after 4 years... _____ returned in Korea... when she came back... she met her brother and best friend... again... she have no choice to leave with her brother... though she hated him for leaving her behind 4 years ago... the thing is... her hatred for her brother are slowly turning into love... not just a brother and sister love... but a romantic love... what will happen to her?? will she really fall in love with Kyuhyun?? Does Kyuhyun feel the same towards his sister?? what if Onew fall in love with ______?? will their ending still be a happy ending??