Lots of girls are flat-chested, which was probably why it was so easy to disguise herself as a boy. :D But don't tell me anything else, I'm not that far into the books yet.

oh. sorry

She said that she always planned to have her as a girl. Like ArcticWolf said, a lot of woman are flat chested (I relate more than words can say XD), and I think Akito wore a lot of layers of men's clothing to cover her more feminine parts- judging by a some images, she isn't really that flat chested.

Lol, low-lives called men.