She is fiercely independent, and is unconstrained by social expectations of her status. And while she couldn't be categorized as a tomboy, she never aspired to be a proper lady as her older sister had.
She's trained in swordfighting and archery, same as her male siblings(I'm assuming). She is quite proficient with both weapons, and better at handling them then more then a few men at House Leventhorp. Even though he is the late king's bastard child, she doesn't exactly hold it against him. I think that they would get along just fine.