Who is Mr. Vercueil (the homeless man) from Age of Iron and what is their importance?

Mr. Vercueil is the homeless man that Mrs. Curren finds outside of her home, and who she eventually allows to stay. Over the course of the novel, Mrs. Curren's charitable act in taking Cercueil into her home is rewarded by friendship..... and having someone around who cares how she fares.