Does my butt look big in this superhero outfit?

I never thought I’d be totally into comics, but I have to say Ultimate X-Men is rocking my world, especially volume 9, new mutants. Emma Frost is fantastic, although I am not sure what use her powers are (her skin turns to Crystal). Angel swoops in and looks like Fabio and the Evangelicals thinks he’s an angel of God. Plus, some underground terrorist organization tries to rid the world of normal humans. Nice.

So, why is it generally accepted for women in comic books to be half naked? And why such exaggerated body shapes in both men and women?