Who is Irana Preveza from A Coffin for Dimitrios and what is their importance?

Irana is a prostitute who owns a nightclub called the La Viérge St. Marie. She lived at a boarding house with Dimitrios, and he became her pimp and brought her new clients, after using her as his unwitting accomplice to blackmail one of her customers. Dimitrios disappeared owing Irana a large quantity of money, and she mourns the fact that she will never get her money back now that Dimitrios is dead.