Bella is the eldest and favorite daughter of the Wilfer family. She is frequently described as being a beautiful young woman, and at a very young age, she was betrothed to John Harmon, or the body that has been found at the beginning of the book by Gaffer Hexam. While she wasn't the happiest about being married off in such a fashion, she did have Harmon's fortune to look forward to, and in the wake of his death, she finds herself quite pitiable, often mourning the fact that she shall have to be poor the rest of her life and how ridiculous it is to be "widowed" at such a young age.
Throughout most of the novel, Bella describes herself as being "mercenary," and reconciles the matter with herself to the point where she is perfectly accepting and encouraging of the title. In spite of her unspoken interest in John Rokesmith, she declines his original proposal of marriage, mostly on the grounds that he is below her and has no money. However, once she is taken in by the Boffins and given nice things and she sees how wealth spoils the good Mr. Boffin, Bella realizes she doesn't need money to be satisfied and happily accepts John Rokesmith as her husband.
Bella is educated and literate, as she is seen a few times throughout the novel reading books. She also is connected to Lizzie Hexam and can be seen as Lizzie's parallel in the novel. Her devotion and high-esteem of Mrs. Boffin, as well, speaks to her character, as Mrs. Boffin is one of the few characters in the novel who are capable of the same mystical literacy as Lizzie.