Brimstone by Callie Hart

The #1 New York Times bestselling romantasy series continues with more drama, higher stakes, and deadly consequences.

Duty. Blood. Honor. Power.
 Saeris Fane doesn’t want power. The very last thing she needs is her name whispered on an entire court’s lips, but now that she’s been crowned queen of the Blood Court, she’s discovering that a queen’s life is not her own. A heavy weight rests upon her shoulders. Her ward—and her brother—need her back in her homeland…but the changes that have strengthened Saeris have also made her weak. Born under blazing suns, Saeris will surely die if she makes her way home through the Quicksilver. Which means that, once again, she must send someone else in her stead...
 
“Keep your mouth shut.  Stick to the shadows. And for the love of all seven Gods, do NOT crack any jokes.”
 
Kingfisher of the Ajun Gate has defeated armies and survived all manner of horrors, but traveling back to Zilvaren with Carrion Swift might just be the death of him. The male just will not shut up. Hidden dangers await them down the narrow alleyways of the Silver City. Unfolding secrets pose impossible threats. Fisher must wrangle the smuggler and accomplish his goals quickly if he wants to see his mate again.
 
A darkness falls across Yvelia. The realm and their friends are in danger. Together, Saeris and Fisher will pass through fire and brimstone to save them.