Jessica is a 29-year-old freelance statistician and single mother living in San Diego. She focuses her energy on raising her seven-year-old daughter, Juno, while taking on odd jobs to make ends meet. Highly analytical and protective of her established routine, she remains skeptical of romance until an impulse DNA test results in an unprecedented compatibility score.

Dr. River Peña is a geneticist and the founder of GeneticAlly, a DNA-based matchmaking service. He presents a somber, private, and serious exterior that often reads as cold to strangers. Beneath his shy demeanor, he harbors a thoughtful nature and a deep investment in validating the scientific accuracy of his matchmaking algorithm.

Felicity is a 34-year-old romance novelist and Jessica's charismatic best friend. She spends her days writing at the neighborhood coffee shop and acts as a vocal advocate for Jessica pursuing romantic risks. Outgoing and enthusiastic, she actively uses her friend's unusual dating situation as research for her books.

Juno is Jessica's seven-year-old daughter. She is a bright, inquisitive child with a passion for science, art, and building elaborate model roller-coasters. She pays close attention to the adults around her and quickly bonds with anyone who shares her intellectual curiosity.

Ronald, affectionately known as Pops, is Jessica's grandfather. He provides steady emotional and practical support, acting as a grounding presence for both Jessica and Juno. He actively encourages his granddaughter to take risks and pursue happiness.

Joanne, affectionately called Nana Jo, is Jessica's grandmother. She offers warmth, childcare, and unconditional encouragement to her granddaughter. Her steady presence stands in sharp contrast to the chaotic nature of Jessica's actual mother.

Jamie is Jessica's absentee mother. She struggles with a history of substance abuse and chronic unreliability. She pops into Jessica's life unpredictably, usually seeking financial assistance while showing little genuine interest in her daughter or granddaughter.

David is the CEO and head of research at GeneticAlly. As the co-inventor of the DNADuo technology alongside River, he fits the archetype of a highly focused scientist. He prioritizes the company's success and impending official launch above all else.

Brandon serves as the head of marketing at GeneticAlly. He acts as the commercial face of the operation, coordinating publicity efforts and press interactions. He aggressively promotes the platform's high-profile matches to generate public interest.

Johan is an octogenarian who, alongside his wife, constitutes GeneticAlly's first-ever Diamond Match. He represents the long-term potential of genetic matchmaking and serves as a living example of a highly compatible relationship.

Dotty is Johan's wife of 63 years and the other half of GeneticAlly's original Diamond Match. She serves as living proof of the platform's romantic ideals, deeply impressing Jessica with her enduring relationship.

Natalia is River's older sister and works as a research analyst. She is warm, teasing, and highly protective of her younger brother, helping to reveal a gentler, more relaxed side of his personality.

Pilar is River's other older sister, currently studying to be a nurse. Open and friendly, she readily welcomes Jessica into their family circle and eagerly shares embarrassing childhood photographs of her brother.

Lisa is the head of customer relations at GeneticAlly. She serves as the main point of contact for new clients, guiding them through the genetic matching process with professional enthusiasm.

Daniel is a barista at the local coffee shop. He observes the daily routines of his regular customers and occasionally shares local gossip about their lives and business ventures.