The beauty of this work lies deeper than just a wonderful looking woman looking out to the other person. The dress was well selected, her hair is well kept, the lighting is perfect, the emotional attachment is brilliant, the aura of this work is breathtaking.
The expression on her face is also a job well done - she's certainly familiar with her work, so good work that. The lighting is also crisp, which adds furor to this piece.
The background is also fairly well kept, and doesn't intervene with the majority of the picture.
Well done, keep taking photographs, and complements to the model.