f(x) - Goodbye Summer(Amber+Luna+Krystal With D.O. of EXO)
(同張專輯主打歌:Rum pum pum pum)
*雖然主打歌Rum pum pum pum也受到許多人的喜愛,不過Goodbye Summer
f(x) - Goodbye Summer(Amber+Luna+Krystal With D.O. of EXO)
(同張專輯主打歌:Rum pum pum pum)
*雖然主打歌Rum pum pum pum也受到許多人的喜愛,不過Goodbye Summer