She walks in beauty, like the night
Of cloudless climes and starry skies;
And all that's best of dark and bright
Meet in her aspect and her eyes:
Thus mellow'd to that tender light
Which heaven to gaudy day denies.
One shade the more, one ray the less,
You can see by the expression of her face and look in her eye that she is full of good  and  evil. 
 The writer is fixated on the physical aspects and beauty of the woman he writes of, ignoring aspects of her character. He is attracted by looks and not who she is. This could be suggestive of the belittlement of women, reducing them to objects, or could be written in order to allow the creation of a person Byron finds most attractive.
She Walks in Beauty