Queen of Night: A Hades and Persephone Retelling (Part Two) (Faeries of the Underworld Duology) by Katherine Macdonald

The courts divided. A heart broken. A lover lost. Reeling from the loss of Hades, Persephone grudgingly takes on the mantle of Queen of the Underworld, a role she struggles to fill. Obsessed with reopening the way to Tartarus and finding her mate, Persephone must balance her responsibilities as queen with following her heart… or risk the destruction of the entire human race. For something is stirring in the pit, and betrayal will come from unexpected places...