Which Adult Fantasy Romance Books Feature Complex Magical Worlds?

I'm always on the hunt for books that blend intricate magic systems with that extra bit of heat, and it feels like the romantasy space has really exploded with options lately. A lot of them have gorgeous worlds, but sometimes the spice feels tacked on, or the world-building gets sacrificed for the romance. The ones that stick with me are where the magic isn't just a backdrop—it's woven into the characters' identities and the central conflicts. For pure, dense world-building, I keep going back to 'A Court of Thorns and Roses'. Say what you will about its popularity, but the seasonal courts, the politics of Prythian, and the way magic is tied to territory and bargains created a framework so many later books borrowed from. The spice builds over the series, too, feeling more earned by the later books. On the more niche side, I tore through the 'Plated Prisoner' series recently. It starts with a gold-touch Midas retelling but expands into this sprawling, gritty world of fae kingdoms and forgotten gods. The magic is visceral and often cruel, and the romantic tension—and eventual spice—is deeply entangled with power dynamics and trauma. It’s not a cozy read, but the world feels alarmingly real. Then there’s the whole subgenre of spicy fantasy with progression or LitRPG elements, which is a different kind of complexity. Books like 'Mountain King' or 'The Half-Orc's Maiden Bride' often have very rule-based magic systems—stats, skills, levels—alongside romantic plots. The world-building there is less about lyrical beauty and more about logical, sometimes game-like, structures. It’s a specific taste, but if you love seeing a character literally grind their way to magical mastery while navigating a steamy relationship, it’s a fascinating blend. My shelf is a testament to how varied 'complex magical worlds' can be, from politically intricate fae realms to systematically brutal monster kingdoms.