Okay the upper body is the right proportions from a female her age that's what I like about this drawning. Her breast wasn't exaggerated for the sake of a good picture.[Never resort to 'ECCHI' drawing style if drawing a female of teens never here are links that shows the exaggeration in play Hinata Hyūga from Naruto she's only sixteen with a DD-cup, Bullet same boat as Hinata and Orihime Inoue she is what like seven-teen and have you seen her rack huge although these aren't the exactly ecchi but for girls their age they have huge Bust.] This is the perfect example of a even proportion of a female.[I'm not saying it's immpossible for a girl to have DD-Cups when their 16-18 but it's not normal either.]