Correct me if I'm wrong but

White sweater: Suju's Manager Oppar
Black "I Trsut" t-shirt: SNSD's Manager Oppar
Red Jacket: SHINee's Manager Oppar
Black pants with orange strips: f(x)'s Manager Oppar
and, my personal favorite

Blue shirt/pants: Exo's Manager Oppar!!!!!

Omfg this is the funniest and greatest thing ever. It's the Managers of some of the most popular groups from SM Entertainment dancing to SHINee's newest song Dream Girl. I now have a better understanding as to why my boys from Exo are such Derps. Keep up the good work Manager Oppar!!! Enjoy