It seems strange that something as loose as a loincloth would be giving her a wedgie.
It's not a wedgie she just has a nice round butt and the fabric that is laying on top of it is very thin and conforming to it's shape. That's how I imagine it...
A few things about the sprite.
1.Try really hard to make sure there aren't any blatant straight pixels as that tends to flatten the depth you are going for. Specifically I'm talking about her shoe straps that are on the calves. Try and wrap the form around the calves. Some things can be straight but not straight across a rounded form. I base this piece advice off of what you would do if you were drawing this on paper.
2. The color for the skin is too pinkish. I think it is anyway. I'm pretty sure my monitor is properly calibrated. Anyway I think you should move a little bit away from the red hue.
3. You are nuts for having 2 different horizontal directions. I wish you the best of luck

Although I suppose that doesn't have to be true for the walk or anything else.
4. I really like her pose and her facial "Style" I like that she has a nose and a mouth and she also has a nose in the profile shots. Good stuff!
Oh one last thing. Please please please do something about your pallet. It's painful to look at(just talking about the pallet grid)
Love it so far! Keep it up!