NOt bad, but I would prefer seeing the girl from the front. With stuff like this, especially concept art - always try to show as much important information as possible, even when having characters interact. The interaction is important, but the STORY isn't as important here other than just telling the story of the world itself. Does that make sense? Also - read the post below about labeling your images. SKetches are OK but I think you rushed the costumed friend ones.