Questions about the fae.

[Mira]

    In my opinion, Mab hasn't totally lost her soul.  However it isn't something she wants anyone to know, because she feels it makes her vulnerable.   She exposed her "humanity or soul" to Harry when Maeve died, admitting that she was indeed human once in Cold Days.  Kringle knows and warned Harry about exposing that fact to anyone because Mab will then do her best to prove to everyone that she hasn't one.

[Cozarkian]

Ya, we apparently changes loads of words just to be contrary.  Ironically, the modern spoken form of English accent in America is actually closer to the original than the modern British accent, which evolved later due to some class warfare.   Other colonies like Australia sound the way they do because they were founded after the pronunciation changed on the eastern side of the pond.  So we speak it better, but still dont know how to spell...

Or we spell better. Take words like pound, mound, and sound. The "ou" has a pronunciation that makes it inappropriate for use in words like mold and color.

[Rasins]

Mab and all Fae who once were human (mortal?) still have a soul.

How dark it is ... that's a different question.