The Female by Invi Wright

The female decline was swift.

Nobody knew why women are no longer being born, but it didn’t take long for men to grow restless and aggressive, hoarding any women they could find and claiming them as their own.
Parents began to hide their daughters, stowing their females underground to keep them safe.
Charlotte, despite her desire to leave, has accepted that she will live out her adult life within the walls of her parent’s home. Tucked away and hidden from the men who would tear her family and house apart to get her.
When the Seekers show up for a surprise raid, Charlotte is one of the unlucky women who are caught. Forced out of her home and thrown into a world that she has only experienced through stories from her parents, Charlotte must learn how to stay alive and serve the three powerful demons who have purchased her.