Overall, I enjoyed Working for the Devil
quite a bit. The world-building was interesting, detailed enough and without massive infodumps. The plot was decent and multi-layered. The magic was at least trying its best to be reasonably original. Japhrimel was hot and alluring, at least to start with.
On the other hand, the writing felt rough around the edges, with too much repetition of specific phrases or descriptions. Japhrimel, intriguing and alluring at first, turned into someone whose possessiveness and insistence gave me pause more than once towards the end. And Dante herself... well, she was my biggest problem, really.
female protagonists who are tough and independent, I really do, but there's a difference between tough and independent and having a chip the size of Antarctica on their shoulder, volatile, aggressive and rude at every possible and impossible opportunity, stubborn and reckless to a fault and basically overall just apparently having a death wish.
That said, I can see myself reading some more of this series. The events of this book should have at least some sort of effect on Dante, I'd expect, so perhaps I would like her better in the next volumes.