While Robin Vote is the protagonist of Nightwood, writer Jane Rule, a Canadian author of lesbian-themed novels, claims that O'Connor is the main character of Nightwood and that his "ironic cynicism and self-pity" set the novel's tone. That this novel is more a psychological work than a literary narrative has been expressed by critics; further, T. S. Eliot wrote in the introduction, "...only sensibilities trained on poetry can wholly appreciate it." In fact it was Eliot and poet Dylan Thomas who fought for the book's publication.
The novel’s prose is dense and richly metaphorical, and two of its eight chapters consist solely of long conversations on the nature of lesbian love and sexuality. [Enotes]
Matthew O'Connor is a transvestite who pretends to be a doctor, delivering babies and performing abortions in "a futile struggle for legitimacy." This effort seems to capture metaphorically the struggles of the women in the novel who all have contact with Robin Vote, with disastrous results. Dr. Connor seems to speak for the women in his philosophical ramblings that serve as the backbone of the narrative, such as this one:
"A man's sorrow runs uphill; true it is difficult for him to bear, but it is also difficult for him to keep. I,as a medical man, know in what pocket one keeps his heart and soul, and what jostle of the liver, kidneys, and genitalia these pockets are pilfered. There is no pure sorrow....There are only confusions."
Throughtout the book, the main character is Robin Vote.