What is the author's style in Killers of the Dawn by Darren Shan?

The language of this novel is relatively simple and easy to read. The author, however, interjects many foreign words to fit into the setting of the novel. The language is from the 21st century but also includes words that are made up to fit the world of Vampires and Vampaneze. The language is descriptive enough that it helps to explain the situations, but is not always detailed enough for the reader to truly understand.