Within the Hollow Heart by Melissa Wright

A hero in need of saving. A curse no kiss can break. The bargain that brings them together—and might bring down the kingdom.

Nickolas Brigham was meant to marry a princess. Everyone said so. His mother, mostly, but it wasn’t the time to quibble.
If he doesn’t marry a woman of station soon, he’ll be tied to a fate worse than ruination. When he’s dragged bodily into a compromising situation, his only choice is to accept the aid of the doe-eyed damsel he chances upon in his attempt at escape.
But Jules is no meek maiden. She’s clever and quick, and has terms of her own: Nickolas must vow to break her curse before the fae prince comes to collect his due. Yes, only that, and the minor feat of fooling the kingdom by faking their betrothal.

Slow-burn and sweet kisses with properly stabby heroines—these regency and fairytale inspired fantasy standalones are perfect for fans of Enchantment of Ravens and Little Thieves.