Siwon and Yoona are childhood friend.They became so close.. even when they grow up they are still so close. Some of their friend are teasing them but they did not mind it because they know that they are just friends and nothing else. but when yoona confesses that she is inlove with kibum siwon felt something deep inside.the feeling of jealousy. and day by day siwon realizes he is inlove withh his bestfriend yoona. what will he do? will he help yoona and kibum end up?