Always good to see the lovely Luba as a base for just about anything (if only her first name didn't sound like a trade name for some sort of lubricant...). You did a splendid job with this, I especially like the watercolor effect (if that's the right word).
The only thing that detracts from it, in my opinion, are the somewhat jagged edges of some of the costume components. For example, the bat logo on her panty is so clean... compare that to her collar. This is just a nitpick I know.