A Monsoon Rising by Thea Guanzon

Here is a summary with spoilers of  A Monsoon Rising

After their political marriage, Alaric and Talasyn remain hesitant and distrustful of one another. During Talasyn's coronation, a group of her own people storms the castle in an assassination attempt. Alaric comes to her aid, and in the chaos, Talasyn ends up saving him in return. However, Alaric’s loyalty to Talasyn does not go unnoticed—his father, the Night Emperor, tortures him in retaliation.

Both Alaric and Talasyn harbor secret plans against each other, fueled by their unresolved tension. Alaric is tasked by his father to strip Talasyn of her light magic once their shared mission to “save the world” is complete. Meanwhile, Talasyn works with her court to devise a way to kill both the Night Emperor and Alaric, ensuring her own survival and that of her people.

Despite these opposing agendas, they are bound together by a shared goal: using their combined magic to forge a powerful stone capable of defeating the World Eater, a catastrophic force threatening their lands. Throughout the book, they struggle to master the intricacies of working their magic together, their practice sessions fraught with friction and suppressed emotions.

At one point, Alaric visits Talasyn at her home castle to continue their magical training. While there, a sudden monsoon strands them together for several days. The forced proximity breaks down some of their walls, and their long-buried feelings surface. They sleep together, agreeing it’s purely physical and devoid of love—maintaining the guise of their marriage as a political arrangement.

After their time together, Alaric is summoned back to his father’s court, separating them for a month. As the Seven Moon Eclipse approaches, heralding the arrival of the World Eater, Alaric returns to Talasyn’s side. Together, they use their combined powers to defeat the monstrous force, though not without cost. Both suffer severe injuries: Alaric gains a disfiguring scar on his face, while Talasyn is left with a permanent scar on her arm.

Even as they celebrate their victory, Talasyn struggles with her growing feelings for Alaric, torn between her desire for independence and the unexpected bond with her husband. During the victory ball, chaos erupts. Alaric learns of a prison break orchestrated by his father’s court, and soon Talasyn’s own court is thrown into turmoil.

The betrayal cuts close to home when Oryal, Talasyn’s trusted friend, is revealed to be a key player in the plot, alongside Talasyn’s own grandmother. Drugged and abducted, Talasyn is taken to the Dominion Court, leaving her fate—and her fragile alliance with Alaric—hanging in the balance.