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

Sergeant Mike is the tall, strong, and handsome Northwest Mounty with whom Katherine falls in love. Sergeant Mike naturally places himself in the positions of caretaker, guardian, teacher and father-figure to the sixteen-year-old girl with whom he falls in love. In fact, all throughout the novel, Mike calls Katherine "girl," showing that he reinforces and welcomes the notion of his role in Katherine's life. Mike is a confident man who knows who he is and where his responsibilities lie.