A Novel length erotic fantasy adventure?

Is there even such a thing? I’m trying to write my own but I was wondering if there are any books out there that are basically like Mistborn or other long fantasy series but with a heavy emphasis on sex and sexual things. Where even the monsters are more interested in fucking the humans rather than killing and/or eating them.

I have seen a lot of hentai manga too with a lot of fun premises but they are basically one shots, they establish a fun concept and then just sort of end. So, any recommendations for books that are beyond the 25-30k word count?