The Raven Warlord — Kristen Gupton

King Keiran Sipesh has always known the day would come when he'd be forced to face down Lord Athan Vercilla. He just never imagined that time would come so soon. However, Keiran finally understands the depth of Athan's meddling in his family's affairs, and he realizes if he doesn't act, it is about to get much worse.
Lord Vercilla has ruled uncontested for more than eight centuries. He's sought to shape the world to his liking in that time, but things are beginning to get out of hand. Keiran was to be molded in his image, but the younger vampire's rebellious streak has proven unstoppable, and his sons have been a chronic source of disappointment.
Now, there is only one thing the Raven Warlord wants in the world, and he's poised to take it back. Keiran is the only potential thing standing in his way, but he should be no more difficult to eliminate than any of the others have been. Athan will reclaim his lost love at any cost, and the consequences of doing so will be absolutely disastrous to the rest of the Known World if Keiran doesn't manage to stop what began ages before he was ever born.

This is the finale of the Royal Blood Books.