Other then the models amazing beauty and the wonderful posing and great contrast and lighting (okay other then everything awesome in the piece ) I think that the lipstick added that absolutely perfect depth to the model. I mean the way the black just encompasses the red really punches you in the face with the meaning of the piece. It looks likes shes cold and sad, but somewhere in there she has this blossoming well of beauty and happiness that maybe hasn't been shown yet cause the one person that could call it forth hasn't come into her life yet.
That's what I got from it anyway. Wonderful piece.