This is a list that I've compiled of every adult romance book I can find with an asexual main character. Any subgenre or space on the ace spectrum is included, including demisexual rep. A few books include aromantic rep, which is noted. I only included books with around 50 pages or more. I have not read every single book on the list, but I did the best I could to confirm that each book has some form of ace rep and is an adult romance. However I can not guarantee that the reviews saying some of these books had ace rep were accurate. Also, I cannot promise that the rep in these books will be good rep.

Here's a link to a public tag with the same books so you can search and filter: https://app.thestorygraph.com/tags/942801cc-340e-4b2c-87d3-9bf81b77f029