Quick explanation 

Junmyeon has been accepted to korea high school with jongdae. They back after 6 years in China. Beakhyun got worried to let her daughter alone so she quit her job and come a long.

Back to present 

Mom i will be fine. suho

I know i just cant let my baby go. Please don't grow so fast. Beakhyun 

I wish that come true but it didn't. Suho 

From now you have to use your new name suho. Beakhyun 

Yes mum i know  PARK JUNMYEON . Oh no i am late to school. I have to go bye mum i see you after this. Suho 

Ok bye be carefully sweetie. Beakhyun 

At school 

Junmyeon enter a class room, she saw jongdae and siy next to him. 

Hi. My name is Park Junmyeon. What is your name? Junmyeon 

Hahaha very funny junmyeon. Jongdae 

What!! Junmyeon 

I hate when i have to use this name. Why the government told us to use our Korean name( don't hate me just for this story) . I liked my Chinese name better now everyone will know my dad is park sehun and take advantage of me. Jongdae 

 At least you don't have to change all your name like mine. Junmyeon 

Ok class please give me your attention. We have new professor and please introduce your name. Hello my name is PARK CHANYEOL. Ok thank you. Not only that we new students from China and please introduce your name. My name is KIM MINSEOK. The second boy, the is given WU LUHAN Junmyeon and jongdae gasp. 

Why he is here!! junmyeon 

Why she is here!! Jongdae