This vid just really got into me. 

SM Managers rocks!!! 

Wonder when will they made their debut? Hahaha.. Kidding 

By the way.. Their unofficial fanclub is 

M.O.P AKA Manager Over Perfection 

That really makes me laugh for 5 minutes non-stop. 

Here is some guide for who is who : 

SJ Manager ~ White jacket 

SHINee Manager ~ Red jacket 

EXO Manager ~ Black Jacket + Blue t-shirt 

SNSD Manager ~ All black 

F(x) Manager ~ Black jacket + Red pants 

So... Who's your bias? ^^