As a surrogate mother, Christophine introduces Antoinette to the Black culture of the Caribbean and instills in her a sensitivity to nature and belief in the practices of obeah. Significantly, it is Christophine's voice that opens the novel, as she explains Annette's exclusion from Spanish Town society; Christophine is the voice of authority, the one who explains the world to Antoinette and explains Antoinette to the readers. With her words gliding from a French patois to a Jamaican dialect and back into English, her command of language corresponds with the power of her words and her ability to invoke magic. She seems omniscient, intimately linked with the natural and tropical world and attuned to animal and human behavior.

Christophine, much like Antoinette and her mother, is an outsider. Coming from Martinique, she dresses and speaks differently from the Jamaican Black people. She is a servant, but, unlike the other Black servants who live at Coulibri, she remains loyal to the Cosway women when the family's fortunes dwindle—an alliance at which the other servants sneer. Like Antoinette and her mother, Christophine becomes the subject of cruel household gossip, although she still commands some household respect because of her knowledge of magic.

A wedding present from the old Mr. Cosway to Annette, Christophine is a commodified woman, but is still fiercely self-willed. She provides a contrast to Annette in that she exercises complete independence from men and implicitly distrusts their motives. When Mr. Rochester arrives at Granbois, he immediately senses Christophine's contempt, and he associates her with all that is perverse and foreign about his new Caribbean home and his indecipherable Creole wife. A threat to Rochester's English privilege and male authority, Christophine calmly monitors his attempts to assert dominance. She instructs Antoinette that "woman must have spunks to live in this wicked world." Christophine adopts an increasingly assertive role in protecting Antoinette when Rochester begins to challenge his wife's sanity. Ultimately, Christophine advises Antoinette to leave her increasingly cruel husband, citing her own independence as an example to emulate. Having had three children by three different fathers, Christophine remains unmarried, saying "I thank my God. I keep my money. I don't give it to no worthless man." Christophine's final confrontation with Rochester establishes her as Antoinette's more lucid spokeswoman.