Tuppence and the Devil

Be Careful of the Company You Keep
Deirdre wanted nothing more than quietly to be left to her studies, but that was never to be. She'd made a pact with the Devil. And ... well, a pact with the Devil was exactly that. Now her life was topsy-turvy, her studies were out the window, and she and her most beloved friend, Lady Isabel, were dragooned into a ridiculous and perilous Quest seeking a nonexistent relic.
To add to her woes, they soon were being pursued by the minions of an angry and vengeful god, and the Fiend, her friend and protector, was nowhere to be seen. How could it get any worse?
How was she going to get out of the danger in which she and Isabel found themselves?