I like all the colors in this piece. Her waist looks too small for her organs to actually be there and her hips seem off as well. The placement of her nose seems off as well, as if it's too far to (her left) the right.
I think you mean her, unless there's something I'm missing about Nami from One Piece. I don't watch the show so that could be it.
A waist is a normal part of human anatomy but the drawing shows it as too thin and the hips too wide. Her back looks a lot angled to show more boobs and emphasize the hips now that I'm looking at it again. That's fine but the effect here is that she's a snake. That's all that I'm saying.