Love the purple lighting. It's the best part, I think, with how it is reflected on the surroundings and on Twily's hair. Beautiful highlights there. And the eyes on Twily and that general expression of wonderment... well, part of why I came to love her so. Also, I do like how you aligned her wing here. And of course, the darker shading on her body helps give it shape very nicely. Also, the shaping of the hair, with those beautiful gentle flowing curves it has about its length.
The only thing that leapt out on me is the outer side of the ear, which seems to go awfully far down. But that's minor, in comparison to everything else being lovely.