So, there I was, watching some Noragami, when I realized...
They have a nice coloring style in the intro!
So, I decided to try out their coloring style for myself on that one pic of Dark I drew a while ago.
Yeah yeah, it's a bit big cause I scanned it with my printer and shiz (also, that's a copy of that pic that I colored, not the original (cause if I mess up then the original is ruined), thus why some parts look like it's been printed)
Basically, Noragami's style of coloring in the opening of an episode is that the character is basically black and white except for their eyes and their signature color on their clothes, thus Dark's eyes are colored and everything that is blue is colored.