Eighteen year old Hirai Momo has no interest in studying, at all. She is a girl who dyed her hair blonde, wears piles of make-up to school and hangs out with her friends until dawn. Her philosophy is quite simple actually, “have fun as if you going to die tomorrow”. But, everything changed when she met Kim Jongin, a twenty-eight year old Chief Executive Officer for one of the biggest companies in Korea.

Jongin and Momo have been friends for a long time. When Momo left without saying goodbye, Jongin is devastated. Now that they are both Idols, It's not easy to be "best friends" again.