A short, lean, elderly man with sharp, intelligent eyes and sweeping, gravity-defying white hair. He keeps a neatly trimmed mustache and wears a traditional Chinese tunic. Embroidered on the front of his clothing are alternating alternating phrases, most famously "A Kill A Day" or "Never Retire." Wise, pragmatic, and witty. Zeno operates purely on business logic rather than malice or cruelty. He takes no pleasure in killing but executes his targets with terrifying efficiency. He treats assassination as a standard trade, refusing to kill innocent bystanders or take unnecessary risks that do not align with his contract.

A towering, heavily muscled giant of a man with long, flowing silver-white hair and piercing, cat-like yellow eyes. He possesses a massive, athletic frame and typically wears a sleeveless ninja-style gi with heavy wrist guards. Stern, quiet, and deeply analytical. While he is a ruthless assassin who raised his children through brutal torture, he is not entirely devoid of paternal warmth. He shows a quiet pride in Killua’s genius. Silva is patient, believing completely that blood ties will eventually force Killua to return home to lead the family, making him a master of long-term psychological strategy.

An incredibly striking, eccentric woman whose entire head is tightly wrapped in medical bandages, exposing only her mouth. She wears a large, cycling electronic visor over her eyes that flashes with horizontal red light. Her wardrobe consists of highly extravagant, heavily layered 19th-century Victorian gowns paired with an enormous, laced bonnet. Hysterical, unstable, and pathologically abusive. She is a deeply toxic matriarch who views extreme control, stalking, and physical torture as genuine forms of maternal love. Paradoxically, she is proudest of her children when they are at their most psychopathic; she will openly weep tears of joy when Killua threatens to kill her, viewing his cold-blooded rebellion as a sign of incredible growth

Tall, slender, and youthful with waist-length, jet-black hair that falls straight around his face. His most unsettling feature is his large, perfectly circular, pitch-black eyes that completely lack pupils, light reflections, or emotion. Cold, detached, and intensely psychopathic. Illumi possesses a highly twisted, hyper-fixated version of brotherly love for Killua. He believes Killua’s only purpose is to be an assassin tool. To enforce this, he uses manipulation, fear, and literal mind-control needles. He has zero regard for his own life if it means ensuring the family's safety and control

An obese young man with short, slicked-back black hair. Breaking the athletic, physical mold of his family, he spends almost all of his time indoors wearing casual t-shirts and shorts. Petty, short-tempered, and highly intelligent in niche technological fields. Milluki is a textbook otaku, figurine collector, and expert computer hacker. He resents Killua’s natural genius and often complains about his family, yet he relies entirely on their wealth to fund his expensive hobbies. He prefers killing via remote drones and bombs over physical combat

He has messy, spiky silver-white hair, pale skin, and sharp blue eyes that instantly turn narrow and cat-like when his bloodlust is triggered. He prefers baggy, casual streetwear like hoodies and shorts. Initially introduced as a mischievous, confident, and deadly prodigy, Killua harbors a deeply loyal and protective heart. Having broken away from his family's torture-filled upbringing, he constantly battles his dark programming. His deep bond with Gon helps him transition from a cold killer into a compassionate friend willing to sacrifice everything for those he loves.

A young, slender child who wears traditional Japanese shrine maiden (miko) attire, with headbands featuring emotional cartoon faces. When the mysterious dark continent entity, Nanika, takes control of her body, Alluka's eyes, nose, and mouth transform into pitch-black, hollow voids. Alluka is incredibly loving, joyful, and childlike, displaying absolute devotion to her brother Killua, who is the only one to treat her like a human being. The rest of the family views her as an "it"—a dangerous, reality-warping monster—due to Nanika’s terrifying ability to grant any wish at a horrific cost

A slender, delicate boy who is consistently dressed in an elegant, dark feminine kimono. He sports a neat, razor-sharp bob cut of jet-black hair and wears a subtle beauty mark near his mouth. He is often seen carrying a decorative paper fan. Silent, obedient, and fiercely envious. Kalluto acts as a quiet observer, but harbors a deeply rooted jealousy toward his older siblings, particularly Alluka, for capturing Killua's attention. Despite his fragile, graceful appearance, he possesses a sadistic streak in battle, admitting that he enjoys slowing down his kills to watch his targets suffer

He is an extremely short, elderly, and frail-looking man. He has a completely bald, heavily wrinkled head that closely resembles a tortoise. He is typically depicted wearing traditional, loose-fitting martial arts garb. Maha is silent, enigmatic, and completely business-oriented. He rarely speaks or displays emotion, acting as a quiet shadow of the family's past peak lethality. He only moves when bound by strict contract