I also really enjoy Aurelia-- as a daughter of a wealthy family, she should be living a comfortable, quiet life, but she wants more. She also is very fond of Nic, and the two have a tentative romance. She is uncharacteristically feisty for the time period, but a lot of fun, and she saves Nic more times than he would like to admit.
While the Praetors are truly evil and are trying to harness magic to destroy the Roman empire, some of the other characters are painted in shades of gray. Nic is wary of Radulf, but is saved by him. Crispus, the son of Valerius, has a different agenda than Nic has. I like it when characters aren't all black and white-- it makes the book more interesting!
Readers who like books like Michael Ford's Fire of Ares (Spartan Warrior series) or Simon Scarrow's Gladiator will find this trip to ancient Rome packed full of great historical details, adventure, and a touch of magic.