Dragons’ Captive by Alex Lidell

For once, I thought being an orphaned slave would keep me safe. Yet when the dragon princes come for their promised bride, Lady Cordelia, they take me too. Why? Because they are immortal assholes who like to hoard.
But when Cordelia is killed, the dragons have a big problem: if they return without a human mate, they’ll lose their throne.
So we strike a deal. I play bride in exchange for my freedom. All I must do is survive the bridal trials, manage the mating mechanics, and remember that dragon royals are killers, not friends.
All I must do is not fall in love.