A Vow of Dragons and Storms by G. Bailey

Dragons don’t exist anymore. Neither do their legendary fae riders…until I stumble into a mansion full of them.
It turns out the last of the dragon rider fae have been locked in a trap, a mansion with no doors, no way to leave for five hundred years, and I’m the first fae to enter. The dragon fae riders know nothing of the world outside or the vampyres who have taken over in their absence, and most don’t trust me.

Especially not Ziven—king of the forgotten Moon Dynasty.
The gorgeous but cruel king demands I enter the Decidere, a ritual for all fae over the age of twenty. It’s a deadly trial in the dragons’ caves below the mansion, and if you’re weak, you’re dead. Ziven marks me as a traitor, and he doesn’t believe anything I say. He wants me to lose. The Sun Dynasty king takes me in, helps me and is kind. With his help, I might last a week.
With Ziven doing everything he can to end me, my ability to escape the mansion seeming impossible, and dragons literally burning the ground at my feet, I don’t know how I’m going to live through this.
You need to be brave. You need to be a warrior…or the dragons will know.
My name is Story Dehana, and I escaped the vampyres, only to find myself trapped once again with a new enemy who might be worse.