Midnight Dance: Whisperer and the Demon King

What do you do when the dead won't leave you alone - and neither will the king who consumes souls?
Clara Peri has never known a quiet life. Since childhood, the dead have found her - whispering, pleading, showing her the things no living person bothered to witness. She has learned to carry their secrets carefully. She has learned to ask for nothing. She has learned, above all else, to make herself invisible.
When the hundred-year peace treaty between the human kingdom and the demon world comes due, Clara is stripped of everything she has ever known and sent across a dark sea as a sacrifice to Azkiel - the Demon King who survives by consuming the souls of the living.
He expects a sacrifice.
Clara strikes a bargain: she will use her ability to speak with the dead and help Azkiel uncover the truth behind his mother's mysterious death. In return, he will stop killing the innocent. It should be simple. But it's not. Because the deeper they dig into the darkness of his mother's past, the more dangerous the truth becomes - and somewhere between the dead and the demon, the lines Clara drew to keep herself safe begin to blur.
Now she must survive a demon world, a king who obsessively unsettles her more than any ghost ever has, and a secret that was buried for a reason.
Some debts are paid in blood.
Some are paid in something far more costly.