Rebecca has been with the firm her entire career. She is quiet and diligent in equal measure. If ninjas needed brilliant property and commercial law nous, then she may have considered that as an alternate career path, silently sneaking into heavily fortified positions and leaving behind meticulously considered documentation. She'd probably also leave behind her car and a plume of black smoke.
Rebecca is knowledgeable in a world where knowing things has gone out of fashion. Her mind is like one of those big-firm law offices with the rows of impressive looking legal tomes lining the walls, except she has actually read them and understood them.