Holly is a young, independent woman living in a brownstone on the Upper East Side of New York City. She relies on the financial generosity of various male suitors and maintains a carefully constructed, elusive public persona. Having survived a traumatic childhood involving abusive foster care, she closely guards her true emotions and seeks comfort in the stability and luxury of Tiffany's jewelry store.

The unnamed narrator is an aspiring, unpublished writer living in the same Upper East Side brownstone as Holly. He serves as a passive observer of her vibrant social life, finding himself increasingly fascinated by her exploits. He acts as a steady, platonic presence in her world, attempting to understand her identity while struggling to define his own artistic voice.

Jose is a Brazilian politician who frequently visits the brownstone apartment. He is highly conscious of his public image and career ambitions. He becomes romantically involved with Holly, representing a potential life of stability and travel in South America.

Mag is a tall, striking model who moves in with Holly. She often drinks heavily when upset and harbors a competitive edge regarding male attention. Her dynamic with Holly fluctuates between uneasy camaraderie and outright rivalry, particularly regarding wealthy suitors.

Doc is an older veterinarian from Texas who has spent years searching for his runaway wife, Holly. He previously fostered Holly and her brother Fred when they were escaping an abusive situation. He approaches the narrator in hopes of bringing Holly back to his rural home.

The Cat is an unnamed feline companion that Holly found wandering near the river. Holly refuses to name the animal, believing that neither of them belongs to the other, though the pet provides her with a constant, quiet presence in her otherwise chaotic life.

Joe operates a local bar frequented by both the narrator and Holly. He harbors a quiet, enduring infatuation with Holly, actively keeping track of rumors about her whereabouts. He is protective of her and serves as a point of connection for the narrator.

O. J. is a short, pragmatic Hollywood actor's agent who previously tried to launch Holly's film career in California. Although she abandoned the audition he secured for her, he remains a loyal, grounded friend who appreciates her sincerity and attempts to offer practical advice.

Rusty is a wealthy, youthful-looking millionaire with a history of highly publicized marriages and divorces. He is a constant fixture in Holly's social circle, eager for attention and easily drawn into dramatic public altercations.

Fred is Holly's beloved brother, with whom she shares a close and protective bond due to their difficult childhood. He is currently serving in the military during World War II. Holly frequently mentions him and affectionately calls the narrator by his name.

Sally Tomato is a mobster currently serving time in a high-security prison. He pays Holly a weekly fee to visit him under the guise of being his niece, using her to pass along coded messages to his associates on the outside.

Yunioshi is a photographer who lives in the same Upper East Side brownstone as Holly and the narrator. He frequently becomes annoyed by Holly ringing his doorbell late at night, though she pacifies him by promising to pose for photos.