Fae's Power: A Fae Fantasy Romance. Queens of the Fae, #5

Griffin O'Shea is Forgotten. Maybe it's a good thing no one outside the prison realm remembers everything he did to earn his place in the dark kingdom. Now that he's back in the world of the Light Fae, he wants to earn their trust, their loyalty, and that means going after the missing prince and princess of Iskalt, children who call him uncle. It means searching through the human realm for a vanishing village only he can see and a book full of dangerous magic and devious secrets that are better left alone. With a human leading the search, Riona at his side, and a profound lack of magic, the chances of finding anything they seek have never been worse. But the odds won't stop them.
Nor will an illness threatening Griffin's life. Even if he has to crawl through the portals and face the king of Myrkur on his knees, he cannot stop. Because there are things worse than death:Watching those he loves die before him. Seeing the realms of the fae crumble into dust. Returning to the prison realm means being forgotten once again. Returning without the book could mean certain death. But when all roads point to war, Griffin has no other choice. The king must be defeated.
His vast army must be stopped. And this time, Griffin wants to be the hero instead of the villain. Fae's Power is the fifth book in the Queens of the Fae series featuring fae out for redepmtion, others desiring revenge, and an entire world that desperately needs to remember the things that have been lost to magic.