The Swindler and The Swan by J.A. Good — book slip

When the goddess Demeter appears at an Olympus gathering wearing Hades' signature color, Hades retaliates by stealing her cherished swan. Upon entering the Underworld, the swan transforms into Persephone, Demeter's daughter.

Seizing the opportunity to vex Demeter further, Hades agrees to help Persephone break her curse. However, he soon discovers that Persephone is not what he anticipated, and their initial scheme evolves into something deeper.

Persephone, who has spent her days as a swan and nights as a woman, finds liberation in the Underworld, where she remains human.

Determined never to return to her previous life, she explores this new world and learns that Hades has much to teach her.