She wasn't allowed to fall in love. Least of all with the father of her betrothed. When Nienna, the Dragon's Heart, sails to Radaan, she knows she's bound for a marriage to a prince she's never met. No stranger to duty, she welcomes the alliance as any princess should. But the prince is not what she anticipated. Kallias, king of Radaan, has spent a lifetime fighting. A treaty ends the war between Radaan and Vellos, but it hinges upon the marriage of his son. If their betrothal ends, the tentative peace will crumble. Yet Nienna is more than he expected. Forged of fire and steel, her responsibility to her kingdom mirrors his own. Nienna needs to feed her people. Kallias needs her dragons. Promises were made. But when duty conflicts with her heart will Nienna be strong enough to resist? Kallias signed a blood oath. Bound by honor and the threat of dragonfire will he be able to stand by and watch her marry someone else? Between Flames and Deceit is a forbidden love, age gap romance. Perfect for lovers of Fourth Wing and Mariana Zapata!