The deities you call aren't always the ones who answer.
Marlow needs to believe she's crazy. The alternative would mean embracing the gift—or curse—shared by her mother and grandmother: she can see angels and demons, including a dark and haunting entity who's been with Marlow her entire life. At least, she believes that's all he is until a fae from the Nordic pantheon strolls into her life and informs her that she's been sharing a bed with the Prince of Hell.
A Prince who's now gone missing.
Before she knows it, Marlow is deeply entangled in a centuries-old war, stumbling straight into a battleground between mighty beings of myth and legend from powerful pantheons around the world. And who will come out on top may just depend on her and the love she never dared to believe in.