Edit: On further thought, there might be an issue with the Fire Lord being subject to another woman that isn't God. Officially, I mean. Would have to do some creative explaining.
Challenge accepted.
The words 'Ahura Mazda' mean literally 'The Wise God'. There is only one God, and we are not a God, but merely His representative on earth. Some would say, we are His reincarnation. However, though the God may be one, there is no such thing to be said about the reincarnations. (We may or may not mention that the deceased Lord Ahura was another incarnation, not a false one, to strengthen our words - depends on whether or not we want to vilify him).
But here is the thing - the God, Ahura Mazda, does not have a gender. The words that comprise the term are 'Ahura', which is associated with masculinity and means 'Lord', and 'Mazda', which is decisively feminine and denotes 'Wisdom'. It would be logical to assume that a single male incarnation can not represent the God in His wholeness. Yes, we are Ahura, their Lord, and Qilin is Mazda, the one whose words we follow, for is it not right for the Wise God to be guided by Wisdom first and foremost?
Their previous Lord understood that he is not whole, which is why he tried to seek Mazda out (certainly he had a higher purpose in mind and wasn't just a lusty rapey freak, was he?), but the fate did not deem his worthy to receive the blessing of Wisdom, and so he perished without being united with his second half. Which is a polite way of saying that he died like a giant flaming moron.
So the representatives of the God are actually both Qilin and Jing, with Jing as a ruler and Qilin as an advisor. They are whole, yet sepatate, which allows Jing to have his own wives and have Qilin outside of the rankings. We have a precedent of multiple incarnations of a single God who sought to have Qilin on their side, so it can be speculated that she must be important to their religion in some way. The meaning of the words supports the theory. Just give it to Xiahou Yu to proofread for obvious goofs, give Ameretat a slap on the ass and get Vahista drink himself unconscious so that he would not hear a word of it until it is over and done.
...I'm having way too much fun with this.