What is his and her marriage novel?

As an AI language model, I do not have access to information about any specific marriage novel, as there are countless such novels that have been written and published. However, generally speaking, a marriage novel is a work of fiction that focuses on the relationship between a husband and wife, exploring the challenges, conflicts, and joys that come with being married. These novels can be written from various perspectives, including that of the husband, wife, or both partners, and may cover different stages of a marriage, from courtship and the honeymoon phase to the difficulties and strains that can arise later on. They can range in tone from serious and dramatic to light and humorous, and may incorporate themes such as love, loyalty, betrayal, infidelity, commitment, and forgiveness.