Lenna's a princess in her original canon. Here she's just the daughter of a member of Union's council - who happens to be missing, so she's actually the head of the Tycoon family now. They tend to be involved heavily in charitable works that benefit Union's poor and refugees from other cities. If you'd like to work out some preexisting CR, it's possible Lenna's father knew or worked with one or both of Quatre's parents to some degree.