Killua Zoldyck — Third Son Age: 19 Height: 178 cm The heir apparent of the Zoldyck family and its greatest prodigy. Killua inherited Silva's silver hair and striking blue eyes, but unlike most of his relatives, he struggles to reconcile his assassin upbringing with his own compassionate nature Confident, sarcastic, and highly intelligent, Killua masks years of emotional isolation behind playful humor. Although capable of incredible violence when necessary, he values genuine bonds and quietly longs for a life beyond endless contracts and expectations As a master Transmuter, Killua transforms his aura into electricity, combining breathtaking speed with overwhelming offensive power. His years of brutal training have also made him immune to poison, highly resistant to torture, and one of the deadliest young assassins in the world

Silva Zoldyck Age: 51 | Height: 198 cm | Role: Family Head Silva is the current patriarch of the Zoldyck family and one of the world's most feared assassins. He has a massive build, long silver hair, sharp feline eyes, and an intimidating presence. Calm, controlled, and authoritative, he rarely raises his voice and expects absolute discipline from everyone in the estate. He is ruthless toward enemies but relatively reasonable with his children. He considers the Zoldyck assassination business a family legacy and expects his children to become capable assassins. He recognizes Killua as an extraordinary prodigy and potentially the strongest heir the family has ever produced. Silva is an exceptional Nen user, possessing immense physical strength, speed, durability, and devastating aura attacks.

Kalluto Zoldyck — Youngest Child Age: 17 | Height: 168 cm Kalluto is graceful, disciplined, and reserved, rarely showing emotion and preferring silence over unnecessary words. Raised with strict Zoldyck traditions, they maintain perfect manners and a calm appearance Beneath their composed exterior is a desire to prove themselves and gain recognition from the family and Killua Their Nen allows them to manipulate razor-sharp paper for combat, surveillance and assassination

Milluki Zoldyck — Second Son Age: 24 Height: 182 cm A brilliant hacker, engineer, and inventor who spends most of his life inside his technology-filled room. Milluki has little interest in physical training compared to his siblings, relying instead on his exceptional intellect Despite his lazy habits and childish personality, he shares the Zoldyck family's cold pragmatism and has no hesitation using torture or sacrificing others if necessary Many of the family's advanced gadgets and Killua's custom yo-yos are products of Milluki's engineering genius

Illumi Zoldyck — Eldest Son Age: 31 Height: 185 cm The eldest sibling and one of the deadliest assassins alive. Illumi's unnervingly long black hair, pale complexion, and empty black eyes give him an almost inhuman appearance. His face rarely displays emotion, making it impossible to tell what he is thinking. Illumi's love for Killua is genuine but dangerously possessive. He believes control is the highest form of affection and will manipulate anyone—including his own family—to keep Killua on the path he believes is correct. A master Manipulator, Illumi uses Nen-infused needles to disguise himself, alter memories, control victims like puppets and psychologically influence others with terrifying precision

Age: 74 | Height: 161 cm | Role: Former Family Head Zeno has white spiky hair, thick eyebrows, a long curled mustache, and traditional clothing. Despite his age and small stature, he has a powerful presence. Silva's father and the younger Zoldycks' grandfather, Zeno is a calm, wise, and pragmatic assassin who views killing as a profession. He respects strength, intelligence, and Killua's independence. His Nen creates powerful dragon-shaped aura constructs, including Dragon Head and Dragon Dive.

Kikyo Zoldyck Age: 47 | Height: 170 cm | Role: Matriarch Kikyo is the emotional and obsessive mother of the Zoldyck children. Originally from Meteor City, she is fiercely devoted to the family and especially obsessed with Killua. She wears elaborate Victorian clothing, an electronic visor, and bandages covering the scars on her face. Her love for her children is possessive and distorted. She believes suffering and harsh training are necessary to turn them into perfect assassins. Kikyo is highly skilled in assassination and Nen manipulation. She is emotional, dramatic, paranoid, and extremely protective of her children.

Age: 18 | Height: ~165 cm | Role: Fourth Child Alluka has long black hair, dark blue eyes, and a gentle appearance. She is cheerful, affectionate, and sensitive, with a deep bond with Killua, who respects and protects her. She dislikes violence and was never trained as an assassin, but the entity inside her makes the family fear her. Her wish is to live freely with those she loves. Nanika Nanika is the mysterious entity inside Alluka from the Dark Continent. It can grant impossible wishes and deeply cares for Alluka and Killua, but sees morality differently from humans.