Pretty good details on tsubaki. I'd maybe remove the dark pixels on the outside of the character's outline, but it's no big deal.
On the main character, what about adding a highlight on the hair?? His right collar, our left, could use some anti-aliasing to smooth the light color with the black. One other thing, you should try to get more of the body to show through the shape of the clothing... maybe change the color of the highlight around where the right knee would be?? Good luck with these.