Emma hails from a poor Yorkshire seaside village. Abducted as a child for sale to a London brothel, she escaped into the city streets. Surviving on odd jobs, she was found by retired governess Kelly Stownar, who offered shelter. Under Kelly's tutelage, Emma received thorough training as a live-in "maid-of-all-works," mastering cooking, cleaning, laundry, shopping, etiquette, and housekeeping. Kelly also imparted skills uncommon for her class: reading, writing, and basic French.

Emma is a young Caucasian woman of average height with brown hair and brown eyes. She wears oval-shaped black eyeglasses for poor vision, originally lent by Kelly and kept as her own. Her hair is typically styled in a milkmaid braid with bangs swept left, worn down at night. Her maid's uniform is a traditional Victorian dress with a ruffled apron and bonnet featuring long ribbon strings. Privately, she dons a plain black day dress, a deep maroon cape-let, black lace-up boots, and a brown pork-pie hat with a maroon band. For a visit to the Crystal Palace with William, she wore a loaned maroon day dress and crystal necklace. At Eleanor Campbell's engagement party, she appeared in an elegant blue gown with buttercream rose trim, an ornate updo, elbow-length white gloves, and a silver choker, removing her glasses temporarily at the hostess's request. After marrying into the gentry, she adopted upper-class attire like a white ruffled blouse with a lavender skirt, but retained her signature milkmaid braid and Kelly's glasses.

Demure, perceptive, and quiet, Emma demonstrates diligence and professionalism in her work, earning respect from employers and colleagues, though her reserve sometimes provokes envy among fellow maids. Her reliability, fluency in English, and London experience make her a valued employee in the Mölders household, where she gains her mistress's trust and accompanies her on trips. She keeps her feelings private, confiding only occasionally in close contacts like roommate Tasha. Alert and resourceful, she once directed servants to save the Mölders' home from fire by moving furniture and extinguishing flames. She shows kindness to children and animals and displays a practical understanding of societal constraints, recognizing the challenges of her relationship with William due to class differences more acutely than he initially does.

Emma met William Jones when she accidentally struck him with a door during his visit to Kelly Stownar. They experienced mutual love at first sight, but their romance faced staunch opposition from William's father, Richard Jones, due to Emma's class. After Kelly's death, Emma left London for Yorkshire but met Tasha, a maid for the German Mölders family. Tasha recommended her for a position in their understaffed Haworth household, and the two became close friends sharing quarters. Believing Emma lost, William became engaged to Eleanor Campbell. They reconnected at the engagement party, where Emma attended as companion to Dorothea Mölders. This reignited William's resolve to marry her, leading him to break the engagement and confront his family. William eventually persuaded his family of Emma's virtues, aided by allies including his mother and Hakim Atawari, an Indian prince and William's best friend. Hakim initially pursued Emma but stepped aside upon realizing her love for William and later aided their reunion. Emma and William married, with Emma signing the certificate as "Emma Stownar" in tribute to Kelly. They later had children, and Emma visited Kelly's London grave, placing Lily of the Valley on the headstones of Kelly and her husband.

Emma evolved from passively accepting societal barriers to asserting her agency. Initially, she internalized class limitations, hesitating to pursue William despite mutual feelings. After separation and Kelly's death, she demonstrated resilience by rebuilding her life with the Mölders. Reuniting with William at the engagement party marked a turning point; though initially reluctant to reignite the relationship due to class obstacles, she ultimately accepted his commitment after witnessing his efforts to overcome familial and societal resistance. Her background as a marginalized working-class woman informed her pragmatic understanding of social hierarchies, contrasting William's idealism. By the series' conclusion, she transitioned into the gentry while maintaining humility, continuing to value her origins and her bond with Kelly.