"When things break, it's not the actual breaking that prevents them from getting back together again. it's because a little piece gets lost -- the two remaining ends couldn't fit together even if they wanted to. the whole shape has changed."

There are many reasons behind a broken relationship.

Change. Change in attitude is one of the reason behind couple's break up. Change is inveitable. Some people like to change with the time and some stays as it is. We can't force anyone to bring change in them.

"If you change the way you look at things, the things you look at change."
 

Distant.  This emotion follows a changed person. A person likes the company of the people thinking alike him/her. Another reason to grow distant with their significant half.

"If one day you realize that we're drifting apart, it's because you've pushed me away...and I let you do that."

 That leads to a fine heart break.

Lim Jihyo

Jihyo is known for her tom-boyish dressing in her whole school. Even though she likes to behave like a boy, she's still girl in her heart — Loving, sweet, and fragile.

She's at her last year of her school.

Almost every other person in her school is her friend. But she only has one best friend, Lee Taemin.

Lee Taemin

Secretly, Taemin is the best dancer in his school, SM High. He is very shy boy, but when he is on-stage, his attitude completely changes into fierce. He is very much passionate about his dance, but he has other responsiblities on him. And due to them he always has to put dancing as his second option.

He is also studying last year at his high school. 

He doesn’t have so many friends, but Jihyo is an exception. Taemin feels comfortable talking to her.