Black and toxic green definitely coolest color combo you can get.
MangaDex Forums
Leffty
Nyanyan444
Why just choose black and white and we have million colours out there?
HoangDinh
@Nyanyan444 what color is manga? Black and white combined can convey those million colours out there.
Angry_Panda
@Nyanyan444 HEY. 
HoangDinh
@Angry_Panda you're purple