Black's myth. Volume two. The key to his heart

In her new case, werewolf private eye Janie “Strummer” Mercado tries to prevent a young girl from becoming a monster, with the aid of her suave djinn assistant Ben Si’lat. But will Strummer gain an intern instead? Then, when Strummer receives a mysterious package, the trail leads back to her nemesis, Rainsford Black--but if Black sent the package, why is he hiring her to find out who did?