I loved the use of first person here! I also think you carried the victorian language well through the piece; it's not a tone that's frequently used in Tolkien-fic but it works surprisingly well. And then it became witch-queen Tar-Míriel. I really liked at the end how she requested a different form; an interesting response from someone who had had her gender used against her before.

I found myself liking Míriel in this story and the voice in which it is told.

I am proud to admit that I made a Maia come that night. -- I love that she's proud of that.

I think it is very understandable that she's worried about getting pregnant, even if she hasn't had her period in a while.

I like how you fitted in her running up the mountain as something Mairon told her to do and how she wants to have the body of a man afterwards, because it's the men that have power. Also that Mairon had intended the Ring for Ar-Pharazon but changed his mind.

I have read fics in which Miriel was the Witch King before and I found this an unusual and interesting take on the idea!

I was really struck by Miriel's voice in this story, especially.

Nicely done!  I don't habitually read either AU or Sauron erotica, but I really enjoyed this one.

Oh I love this. The voice of Tar-Miriel is excellent and the sort of factual way she goes through what happened, like making a record of it. A fascinating exploration of Sauron's time in Numenor--and Witch King Tar-Miriel is fantastic.