The Boarding House is one of a series of stories from The Dubliners by James Joyce. There is a recurring theme as the characters try to escape their mundane, restricted, morally-lacking existences within the confines of Mrs Mooney's boarding house.
Mrs Mooney has escaped her abusive marriage, managing to get a separation agreement from the church. Divorce would be out of the question. The reader then expects much from her who has had to make many sacrifices to protect herself and her children from their meat-cleaver-wielding father. Suspense builds as we see that Mrs Mooney is a strong female character but, nonetheless, she is still subject to the morally deficient environment in which she lives. She contributes to the perpetuation of the manipulation of others and is called "The Madam" by the boarders, inferring her contribution to the baseless, "perverse" society.
James Joyce wants people to understand the "moral history" of Ireland and the contradictory, religious messages from within. Love and marriage should go hand-in-hand but in this world the one is absent from the other.
Mrs Mooney is actually doing what she thinks is best for her daughter who is also trapped in this environment. She is too common to improve herself so marrying well is her only way out. It seems that Bob Doran is the only option from those men available. She certainly has had "the run of the young men" in the boarding house but they are "only passing the time." Taking advantage of Bob Doran does not phase Mrs. Mooney and he is trapped in this same mundane existence himself so, in fact Polly may provide him with a way out of their "paralysis" that is their life.
The suspense builds as we watch the hapless Bob Doran, effectively seduced by the "wise innocence" of Polly, deal with his conscience and his need for "reparation."