Fantasy Sorceress takes men's virility, girl servant and unicorn

So this novel I read when I was pretty young so the details are shaky but here they are as best I can remember them.

I recall that the protagonist is a young woman is who almost always hunched over, because there's a constant burning or twisting pain behind her navel and thinks that she's ugly and worthless. She was kidnapped (I think) as a very young child and raised to be the servant of this old and ugly witch or sorceress. The witch/sorceress actually uses a broom to fly around on.

There's a scene where the young woman sees the witch make the handle of the broom resemble a penis. Which she then animates to ... masturbate with.

Later the young woman sees the witch/sorceress use her magic to make herself look young and beautiful. The witch/sorceress flies off and the young woman follows her. She sees the witch/sorceress seduce a man and after the man climaxes all his life force or virility or youth becomes the witch/sorceress's.

This is where I get fuzzy. I believe there's a guy the young woman sees around and falls in love with from a far. And the she saves him from the witch/sorceress only now they have to go on the run. They come across a unicorn and the young woman rides the unicorn for the rest of the story when they have to run away.

I think there's a jewel or magical object hidden in the young woman's body that causes her pain. And is why the witch/sorceress kidnapped her - to hide the object in a living person and use it's power later on.

After it's removed and the witch defeated. She rides the unicorn for one last time. When she climbs off the unicorn - she sees her menses blood on it's back. The unicorn tells her that they'll never see each other again because only a maiden who is innocent and hasn't yet bled can see unicorns.

Hope you guys have a clue because I don't even remember what the cover looked like.

All the best!

The Unlikely Ones by Mary Brown?https://books.google.com/books/about/The_Unlikely_Ones.html?id=pmIWkAd9iI0C

It's been a LOOOOOONG time but this might be one of Tanith Lee Unicorn trilogy? I read them a billion years ago and I remember them being very odd and transgressive.

In order, Black Unicorn , Gold Unicorn , Red Unicorn.

I just read Black Unicorn and can eliminate that as a possibility. Since the girl escapes her mom-witch in that one, I think it's unlikely to be either of the followups, but I just got Gold Unicorn from the library, so at least I'll find out soon!

>2 sueelleker:, touchstone: The Unlikely Ones by Mary Brown. Haven't read it myself but the reviews make it sound like a match.

Have read The Unlikely Ones, and it's spot-on - 99% certain sueelleker got it.

>2 sueelleker: >5 Cecrow: Seconded/ thirded.