You might want to consider not bolding your text in the future, so you have means of putting emphasis on parts of your text if need be.
It seems Ulquiorra's wings are pretty much just normal cartoony batwings, and yet you went to great lenghts to add all kinds of textures. I wonder why?
The first try has a somewhat typical hairy look that some try to pass for feathers when they don't want to draw them. It doesn't really take into account lighting or really any shapes inside the form.
The latter ones are vastly more interesting thanks to the divided layers of color, but the second, third and fourth all look like they have scales, which is not really what the character has.
The fifth one turns these scales into looking like bark, which isn't much of an improvement but certainly an interesting effect for something more appropriate.
Overall, my advice is... Decide whether you want directional shading and whether you want to mirror your sprite. Regardless of your choice, you should at least put the area that connects to the back in shadow, so there is a sense of dimension to the wings. Also plan out what the wings are actually shaped like, where the bumps are and such. From the few pictures I saw, I assume he has pretty typical batlike wings which means the fingers form specific bumps on the wing surface, and the skin stretches smoothly between them.
Not sure what else to say regarding the fur, maybe hint at it with the edge of shading rather than adding random furry shapes. (if you are going to add those details)
