Girls with bodyfat levels that low present an interesting dilemma.
In order to get that lean MOST women sacrifice substantial breast mass.
If you are okay with smaller natural breasts, you have no problem.
If you're okay with insecure women dealing with smaller breasts by taking steps to have unnatural, painful looking half-grapefruits crammed into their upper torso .... then you have no problem.
If you understand that human history didn't begin in the last 5 years and that there have been looks other than 5% bodyfat on women thoughout all of human history...then you may have other ideas.