I edited the list to groups I listen to. There's probably more lol

15&: Yerin
2AM: Jinwoon
2NE1: Dara
2PM: Nichkun
4minute: Hyuna
100%: Haven't picked yet
After School: Nana
Alphabat: haven't picked yet
Bangtan: Jungkook
B.A.P: Zelo & Yongguk
B1A4: Baro
Beast: Yoseob
Big Bang: G-Dragon
Block B: No bias
Boyfriend: Minwoo
BtoB: Peniel
C-Clown: KangJun
CNBlue: Jonghyun
Cross Gene: Shin
Dalmatian: Daniel :/
DBSK/DB5K: Changmin
F(x): Luna
FT Island: Seunghyun
Girls' Generation: Sooyoung
Hello Venus: Lime
Infinite: Hoya
Led Apple: no bias
MBLAQ: Thunder
Mamamoo: haven't picked yet
Miss A: Min
NU'EST: Baekho
Rainbow: Jae Kyung
SHINee: Key (i say him but it's all of them)
Shinhwa: Minwoo
Sistar: Bora
Smash: no bias
SS501: Hyunjoong
Super Junior: Donghae
Tasty: you CANT ask ppl to pick here
Teen Top: No bias
T-MAX: Yunhwa
Trouble Maker: BOTH
U-Kiss: Dongho :(
ZE A: Kwanghee

And my ultimate bias alongside SHINee, Jung Joon Young <3