She's very cool! I can't help but think of jazz clubs or something when I see that top-hat and classically cool costume of her. :3
Her expression is calm, and beautiful. I'm also a fan of the details surrounding her, from the messy but well-used bookcase and the computer screen showcasing a work *wink* in progress! My only gripe is the chair. It's just...strange.
A girl like that could turn weakness into hardness rather quickly I think Love the fact that you don't overdo the blending and let the brush do the job, particularly the clothes and the bookshelf. (my weakness!)