Cosplay - Bridal Ryuko by Disharmonica/Helly Von Valentine

Well, it's more-so the fact that the shape, overall curvature, and skin-shine of her body, along with fact there's no blemishes, spots, or slightly jutting bones to it, that I'm finding incredibly appealing.
Basically, the fact she looks incredibly close to an actual anime character, but as a real person, is what I find attractive about this image.
Though the fact she also holds to a standard of mixing sexiness with elegance as you've said definitely makes this even more appealing than it already was.