Poison Fruit - Jacqueline Carey (2014) Ace

The third, and perhaps final installment of the Agent of Hel series.  Daisy Johannssen has to navigate not only her love life, trying to decide between a werewolf and a 600 year old Ghoul who used to be a Bohemian Knight, but try to outwit another Hellspawn and prevent Persephone from taking Little Niflheim from Hel.  In the end, she makes everyone proud, even her demon father, by bargaining with God for the good of everyone.