Who is Atenou from Mrs. Mike the Story of Katherine Mary Flannigan and what is their importance?

Atenou is Chief Mustagan's best hunter. When he suffers an abscessed tooth, Mike pulls the tooth, and Atenou goes on to sell his Indian superstitions regarding his tooth of wisdom to Ralph Peters, the shoe salesman from Detroit, Michigan. Later, Atenou delivers the bad news of those killed in the forest fire.