Hecate the Witch

"After stumbling into a pet cemetery, Hecate meets Melinoe, who calls herself a ghost herder. She is in charge of leading the ghosts of pets and other animals to the River Styx in the Underworld. But Melinoe doesn't notice when one of her ghost animals follows Hecate home! More and more of the lost ghosts gather with Hecate, and she learns they have unfinished business left on Earth and refuse to enter the Underworld"--