What a wonderful photo you have here. Composition is perfect, model attractive and the title really explains her expression to me. I also love the hair covering her other eye completing the mystery of who this young lady is. Bravo!
Good colour, detail, depth of field. Does it work square? ... I'm not completely sure: the jaw line is perhaps what bothers me - it seems to upset the balance of the image slightly. Your placing of the visible eye dead centre really works though - I think in square the centre point of the imagae becomes much stronger.
The small bit of the white of her right eye poking through her hair is disctracting to me. I find my eye drawn to it rather than her beautiful other eye that is visible. I like the idea of having only one eye showing. Perfect focus and clarity, especially in the eye. I would have cropped a little more off the top and left a little more space under her chin.
great eyes, or should I say I...I find the hair over the eye a distraction...she has such a stunning blue, that you could have really made them a feature...the rest, is wonderful