Who is Mademoiselle Noemie Nioche from The American and what is their importance?

Noemie is a young painter. Newman meets her in the novel's first chapter, and she overcharges him for a painting the first time they meet. Newman is under the impression that he can help Noemie, and he offers to give her enough money for a dowry if she will paint him a series of several pictures. Noemie doesn't reject the offer, but she doesn't begin the project either.