Who is the friend to Yang Jae Won  (Choo Young Woo ) eat candy al the time in every sceen. He is cut and i havet seen him Before in any drama?  

https://kisskh.at/people/504-lee-jung-jin

Is it this guy? He is the only one in cast list as 'Jae-won's friend'

It’s the aneathesiologist, dr park.