Jiyoung and Dongwoon are best friends.

A long time ago, Dongwoon was shy, but Jiyoung talked to him and played with him enough to the point where he was comfortable.  They both liked going to the park, so every Saturday they would go, since 6th grade. 

Now that they were in High School, Dongwoon and her didn't talk much during the week.  

They didn't drift apart, simply, Dongwoon had older friends.  Five boys who were involved with bad things, like fights and gangs.

Jiyoung knows what's good for her, so she keeps a distance.

Never the less, Dongwoon and Jiyoung are best friends.