The Pearl Queen by M.J. Marstens

Zia Al-Qamar was born a dirty orphan and will die a dirty orphan.
But her life takes an unlikely turn when her best friend loses a bet against none other than the prince of Seawall.
His prize: her.
And, suddenly, Zia’s mundane life becomes an entanglement of palace intrigue, politics, and the attentions of four men.
As if her love life were not complicated enough, Zia discovers that she is has been marked by the goddess, Luliwa, as the true queen of Seawall.
A mark that places a bounty on her head and a death sentence as her fate.
Now, Zia must fight for life, her men, and her people if she wants to win against the dark magic that ensorcells Seawall.
Will she succeed and find her happily ever after?
Or will Zia die just as she was born—alone with nothing and no one.