Hae Soo is one of the best student in her school . Due to some problems, her grades isn't good anymore . 

In order to save Hae Soo's grades from dropping down, Saeron and Joohyuk planning to do something without Hae Soo knows . 

Will Hae Soo be strong to face up her problem with her father? 

Will her own bestfriends be there to help her? 

Who is Minhyuk and Changkyun to Hae Soo?