interesting version. but damn - HOW?
Rachel is just a nurse at the academy under Anders, who herself is under Shirohima. consider it a leap over two heads. Who should Rachel present herself as to Jira in order to become her client? Moreover, a client probably no less powerful than Shirohima. well, it seems to me that when you have two clients, two owners, and their interests intersect, then whose interests will be more of a priority for you? that's what I think too, if Shirohima is more powerful, then her interests are more of a priority, at least by the fact that her punishment can be much more terrible in consequences.
or Rachel is actually much more powerful and proved it to Jira, and her game of a weak nurse (remember the scene in the medical office of the academy) is just a game, a cover? oh yeah, if by the name Rachel we mean not the nurse-host herself, but the demon that lives in the nurse - then everything fits.