Demon Lord of Elysium

When Pucorl, the puck who’d possessed a 21st century Mercedes van, turned the demon Beslizoswian into roadkill on a battlefield outside Paris in the year 1372, he didn't know what he was getting into. How could he? No puck had ever slain a Demon Lord before. But Themis the goddess of proper behavior has determined that Pucorl is now the proper lord of Beslizoswian's Caverns of Torment. And what's a puck-enchanted van with a crush on his mechanic supposed to do with Caverns of Torment?
In this third book of the Demon Rift series we get a look at how things work on the demon side of the veils between the worlds—and how adventuring looks to the servants who go along to cook the meals and take care of the wagons. And how a demon in the form of a dinosaur ended up the majordomo of Carl's Not So Bad Caverns.
We also learn about what's going on in France and England while Pucorl and the twenty-firsters are in Constantinople. We meet a few gods, make a few deals, and even see a truly magical kiss and some of its consequences. All in all it's a fun romp through the magic of Pucorl's lands in Elysium.
And if you don't already have them you'll want the first two books in the series: The Demons of Paris and The Demons of Constantinople.