my first impression while looking at this picture was distance, that she is mental absent, maybe thiking of a strong emotional moment in a movie she is watching at the moment.
this feeling IMHO is well created by showing us the model in this pose, not looking at us, but also not completely away from us; with her face silhouette clearly the focus of the picture. her closed eyes and and body posture, which is somewhat relaxed gives me the impression that she is focussing clearly on herself. speaking of focus; the strong light casting that string shadow on the right handside and creating that beautiful contrast of the dark shadows on the left in opposite to her bright skin create a string focus on the model. just the dot of light on the top, pointing in the oppsosite of her face direction, disturbs this focus, creating an interesting tension in the picture. the colours are well chosen, there is really an athmosphere of an old cinema .
regarding the model, you have chosen an interesting pose in an interesting location to highlight her beaty in an interesting way. her pose leads the viewers eye in a twisted path through the picture. my eyes wandered from her feet up to her knees, down to her bottom, up to her head, to the left in her own viewing direction, just to be distracted a bit by the arrow over her head [which i think is chosen deliberatly]. her body is beautiful, and this pose, showing only a hint of her beauty, but enough to see that she is a very sexy person, is IMHO truly erotic. as is her outfit.
thanks for sharing this work, i like this picture very much, but unfortunately i have no idea what you could have done better. this picture is good as it is .