Originally I gave this 3 stars, and that's mostly because the second story "Sooz" just felt so out of place, tonally

(due to the unnecessary sexual assault)

and because it seem to drag for too long.
But, the more I thought about it, the more angry I got, so I went back and gave this 1 star. I am left with this feeling that I wished I never-ever read this book, because how it has tainted "The Last Unicorn" for me. I hate it that going forward, I won't be able to read that fantastic book without remembering what happen to Sooz and what was insinuated to have happened to Molly Grue in that Novella.
Oh, Beagle, why couldn't you have left good enough alone? If that story was set in a different world, with different characters (and, to be honest, they might as well have been given how little it relates to "Two Hearts") I might have been able to accept the story for what it was. But, nah...I just can't. To me it feels akin to JRR Tolkien, after writing Lord of the Rings, followed it up with a "Game of Thrones novel" that just-so happens to be set in Middle-Earth.

How I think Beagle could have made

the sexual assault

"work" is to have had it very ambiguous and leave it up to the reader to interpret it how they will. The trauma could then take an almost literal-nightmarish quality, which could suit the darker-side of the Fae world, and we, the reader, can get as confused and unsettled as Sooz is as she stumbles through it. The classical paintings, 'The Nightmare' (Huseli) and works by Hieronymus Bosch come to mind.