The Shadowbound King: Realms of the Covenant, Book 2 by Amy Pennza
There are elves and humans. A girl lives close to the Elf kingdom. The capture her because they want something for her father. Instead they end up falling in love. It didn't seem to matter that there were two guys that were already in love with each other, they freely add the girl also. And in an epilogue there is child. The bit of plot is just enough to provide endless gay and straight erotic scenes. Sex becomes just an activity done for pleasure. Being parents or reproducing seems just incidental. This attitude could explain why people are just not having kids. Why bother doing the hard work after the pleasure? Will humans eventually bread out the desire to reproduce?
