Opal Smoke (Opal Contagion Book 1) by Stephanie Fazo

A thief is the only one who stands between her people and complete annihilation. Liss is a Soul Sorter who can sense any emotion a person is feeling. She uses this talent to steal jewels and dragonhide wallets to help provide for her people, the Extended. A side benefit of her thieving is that she gets to empty the pockets of the wealthy Lagonians, who shun the Extended for the deadly disease that runs in their veins. When the Lagonians announce that they’ve developed a source of immunity, they are no longer content to just ostracize the Extended. The Lagonians plan to eradicate them. The only way for Liss to save her people is if she can pull off her biggest heist yet and steal the secret to the immunity. What is already a perilous mission is further complicated when Lagonia’s infamous Chief Assassin is tasked with taking Liss out. Entangled in his own web of deception, risk, and a fight to survive, the assassin cannot fail. One truth becomes clear. If either hopes to succeed, the other must die.