[danim]

Yes, It's possible...I think It depends from the mammary glands, some woman have well developed mammary glands (the fat will add volume too obviously).
I see many girls skinny and with big breasts..I know a girl who had big breasts, she lost weight because of a very terrible period in her life and became skinny , but her breasts weren't so little maybe a B cup..today she has gained weight and her breast is still big as before (a D cup more or less). But I think that NBE expecially massage do THIS work, helps to reach the development we have not accomplished during puberty....

You are right. But we need some fat % to achieve bigger breast, many girls who suffer from anorexia have lost their breast for example.