Holy shit, this is so boss, dude! And in an interview, Kubo-sensei said that Grimmjow's coming back in the future. That's awesome, since he was one of my favorite characters. Maybe after the Fullbring arc, or some time after that...?
I know his face is supposed to be serious but this picture made me want to laugh when is saw it. The coloring is slightly notisable, but I can't say anything more because I can't do any better. I'm favoriting this because it's sooo awesome, you truly captured his expression.