Pin Up Inverno Pretty good.
Looks good to me. I like the position her hand is in, it's a hard one to draw, and you did it beautifully. Not much else to say, I'm not really an artist so not much advice I can give on improving your art style.
And I don't see how anyone could think she looks fat. If you made her any skinnier she'd be another anorexic-looking anime chick. Therefore, I thank you for making her look like a healthy human being.