Bride of the Sea King by Lola Glass

I kissed the King of the Sea, so he made me his bride.

He’s offering me everything I could ever want. Good food. A castle. Immortality. Endless numbers of books to read.
But in exchange, he expects to breed me.
His people are dying out, and they want me to help boost their numbers.
When I immediately refuse, he doesn’t protest or try to force me.
Instead, he decides to win my heart with every bit of power he possesses.
The more I argue with him, the harder he fights. And the harder he fights, the more I want to give in.
I’m the sea king’s bride… and if I can’t stop falling in love with him, I’m going to lose myself in him entirely.