Let me first say that I really like this piece. I feel like you convey the idea of a youthful, cute, innocence without needing to sexualize a female character. The idea is called "Moe" in Japan and is invokes a sense of fatherly or big brotherly affection and a want to protect. So awesome work. Now as far as the critique portion it lays in the face, or more importantly her right eye (or her eye on the left side from the viewers perspective) Due to the catch-lights in the eyes (the light highlights) and the bangs it make her appear like she has a slight lazy eye. Like I mentioned it is slight, and only slightly detracts from a otherwise fantastic piece. Having looked at the piece a few times and measuring it by eye it seems that you have followed some form of ratio rule either through measuring or just by innate talent? So may I suggest opening the bangs a little? Even playing with the placement with the eye itself while it would mess up the symmetry would allow you to correct the appearance of the eye. One other suggestion would be to tilt her head slightly which would allow her hair to move to the left (viewers perspective) and open up her eye to correct the eye. Once again this is a fantastic piece and I am nit picking.