I'm just sitting here waiting for someone to mention 'Daughter of the Pirate King'. Because, wow, was that a letdown on the slow burn front. It gets recommended a lot for pirate romance, but the enemies-to-lovers switch flips way too fast for my taste. The adventure is fun—she's deliberately captured to search her captor's ship—but the romantic tension deflates quickly.
If you want a slow burn that actually smolders, I'd point you toward 'The Salt Roads' by Nalo Hopkinson. It's not a straightforward romance; it's a complex, multi-perspective historical fantasy following the lives of enslaved and free Black women across centuries. The pirate element comes through in the section about Jeanne Duval, and the relationships, including a romantic one, are deeply woven into a struggle for freedom and identity. The 'burn' is in the emotional resonance, not just will-they-won't-they.
I've always had a soft spot for pirate romances, and few authors capture the swashbuckling charm and fiery passion quite like Johanna Lindsey. Her 'Gentle Rogue' is a classic—full of adventure, witty banter, and a brooding pirate hero that’s impossible to resist. Another standout is Lisa Kleypas, whose 'Blue-Eyed Devil' blends historical romance with a dash of piracy, though her 'Wallflowers' series also has some sneaky nautical themes. If you want something grittier, Celeste De Blasis’s 'The Wild Swan' has pirates woven into its epic family saga. These authors have a knack for making the high seas feel romantic and dangerous in all the right ways.