So, I just finished "Who Are You School 2015"
I didn't like much the lead couple, I couldn't decide between Han Yi Ahn and Gong Tae Kwang :p but that it's not the important part, the drama tells the story of a student, Lee Eun Bi, who suffers bullying from her classmates, especially one girl. Because of that, she decides to commit suicide.
In another hand, there is other girl in a different school who is very popular and have many friends but seems to have a little secret, her name is Go Eun-Byul and she's identical to Eun Bi.
The day that Lee Eun Bi jumped from a bridge, Go Eun-Byul disappears, and only one of them is found.