Character's  

Jung Soo Jung  -

AKA Krystal Jung

Krystal is very smart and a top-student in all her classes, she especially stands out because of her amazing English and she only accepts the offer to attend to S.S. because she wants to relive her highschool moments, but she’s very disappointed when she finds out that the school is all about her idol-life. She's the only member in F(x) to accept the offer for S.S. and she feels a bit lonely because all her members and her one and only sister aren’t there with her but that changes soon when she gets close to  Kai. When she signs up for Extra Dance Class she meets Kai there at the first practice and from then on they start to get closer and closer. They Became Bestfriend.

Lee Ji-Eun  -
AKA IU.

IU is a really bright and bubbly person who instantly fills the room with joy when she comes in. Her reason for accepting the offer to attend S.S. is that she wants to meet new people, she has no intention of liking someone, or even fall in love but once she meets Baekhyun she finds herself laughing always when the boy is around. She’s really amazed by his vocals even though she isn’t sure why and she even starts searching for him online. IU thinks she starts to like him but there’s one other person that can make her laugh like Baekhyun: Park Chanyeol and she kind of feels something for the cute giant too... 

Byun Baekhyun  -

Baekhyun is a really smart, funny and cute guy but he can be really stupid sometimes. He doesn’t want to go to S.S. at first but since all the members are going he goes along and once he meets IU he has no regrets. After a while he figures that he likes her more than ‘just a friend’ but he still has feelings for Taeyeon after their break-up even though he’s really into IU and finds out that him and her have more in common than him and Taehyeon ever had... He keeps his little crush a secret from the other members because he’s afraid it’ll go public otherwise...When the both of them match up to sing a duet he mixes her song, the one he has been practicing, with one of Exo’s songs.
 

Kim Joonmyun  -
AKA Suho.

Suho is a very smart guy, he knows how to have fun and he’s really protective: he’s basically a sweetheart deep inside but he hates expressing his feelings so he comes off as really cold and even mean sometimes. Suho is really careful to protect s and himself not to get into scandals and stuff, so when he meets Eunji at his first day and they get into a little accident he gets really mad and they have a big argument. From then on every time they’re paired up they do nothing but fight, all day. However when Eunji talks to one of the Exo-members Suho finds himself getting mad at her and starts arguing even though he isn’t sure why. Ever since he has met Eunji all he has been doing is talking about ‘not good’ or even bad things about the girl and he’s always focussed on her but after that argument he starts to notice how she laughs and how she talks and he gets quite mad inside when he’s thinks she’s gossiping about him...

Eunji is a very nice girl who’s really outgoing, she kind of attracts danger but she’s also very smart and one of her hobby’s is to to mock and annoy people. With Suho she likes it best: all she does is mock the boy and make sure he’s looking so that he gets annoyed. She basically hates Suho to death but that changes when he saves her life from danger... however, she will never admit to him how thankful she is and she still acts as mean towards the boy as she did before. Later, when her life is in danger again, she gets saved again... however  it’s not by Suho this time, it’s Xiumin. Eunji and Xiumin are getting closer and closer after that, they become really good friends but Eunji notices she doesn’t fall for him.