The Kindred's Curse Saga Collection 3 Books Set By Penn Cole(Glow of the Everflame, Spark of the Everflame & Heat of the Everflame):

Glow of the Everflame:
With the threat of war looming ever closer, Diem Bellator must now survive the next thirty days by forming a devil's bargain with her sworn enemies, the royal family of House Corbois. As she dives further into the world of the Descended elite, old prejudices are challenged, and new loyalties blur the line between friend and foe. While Diem fights to save her people, the secrets her missing mother left behind become increasingly hard to ignore.

Spark of the Everflame:
All her life, healer Diem Bellator has yearned to escape her tiny village in Emarion, a realm ruled over by cruel demigods known as the Descended. Although her parents have always tried to shield her from their brutality, Diem's world changes forever when her mother goes missing, leading her to uncover a dangerous secret that links her family to the dreaded Descended in ways she never imagined. The journey to unravel the web of mysteries Diem's mother left behind is long and treacherous, and it soon leads.

Heat of the Everflame:
After her disastrous coronation, Diem is now at the centre of the conflict between the Descended and the Guardians. With her newfound friends - and the man she's falling for - on one side, and the mortals she vowed to protect on the other, Diem must walk a careful line to save the people she loves from one another. When the mystery of her unusual heritage starts to unravel, it sends Diem and Luther on an unexpected journey across the realms.