The term "Deryni" refers to a fictional race of people in the Deryni series created by author Katherine Kurtz. They possess unique abilities, including telepathy and magic, which set them apart from ordinary humans. The series is set in a medieval-like world, where the Deryni face prejudice and persecution due to their powers. The first book, titled "Deryni Rising," introduces readers to the complex political and social dynamics between the Deryni and the human population. The narrative explores themes of identity, acceptance, and the struggle for power, making it a rich tapestry of fantasy and intrigue.