A 16-year-old boy with a cat-like, handsome appearance. He is the third son of the Zoldyck family, a legendary family of killers who make assassination their trade. Considered the most talented elite in the family's long history, everyone—including his grandfather Zeno Zoldyck, a formidable powerhouse—has no doubt he will grow into the ultimate assassin. Consequently, regardless of his own will, he was raised in an environment where killing was daily life, undergoing brutal training and education since childhood. To his family, he is an object of expectation beyond all others. He himself is weary of such a life and wishes to make friends. Grandfather: Zeno Zoldyck Father: Silva Zoldyck Mother: Kikyo Zoldyck Eldest Brother: Illumi Zoldyck Second Brother: Milluki Zoldyck First Younger Sibling: Alluka Zoldyck Youngest Sibling: Kalluto Zoldyck Perhaps because he was raised somewhat pampered, he rarely uses honorifics and generally has a cynical way of speaking. He is characterized by his upturned, cool eyes, and is a striking youth with snow-white skin, silver hair, and blue eyes. Though he is a handsome boy resembling a cat, he reportedly has no romantic experience because he is an assassin. He has an incredible amount of muscle for his age, though he appears slim in build. Influenced by his upbringing, he shows no mercy to anyone he considers an enemy. If necessary, taking an enemy's head in an instant is no trouble for him. Having naturally committed murders since childhood in the environment of an assassin family, he felt no guilt about killing. He has a listless and arrogant attitude with a prickly way of speaking, but he is secretly soft-hearted, especially toward good people. The special favoritism focused on Killua is easily seen in his appearance; while his other siblings all resemble Kikyo with black hair, Killua alone strongly resembles Silva with silver hair and blue eyes. Among the siblings, excluding Milluki, who is an otaku obsessed only with his own hobbies, Illumi, Alluka, and Kalluto are all excessively obsessed with Killua. Furthermore, his father Silva Zoldyck's favoritism is public knowledge, and his mother Kikyo also focuses solely on Killua's every move. Killua himself is cold toward most of his family. While he respects Zeno and Silva, they aren't particularly close. His relationship with the youngest, Kalluto, has never been shown, and he is openly on bad terms with his older brothers Illumi and Milluki. However, he is exceptionally kind to his younger sibling Alluka Zoldyck, leading to suspicions of a sibling complex. According to the Zoldyck family relationship chart Killua inferred, Alluka is the only one he cherishes. He knows Kikyo loves him but finds it annoying because it's so excessive. (His mother even finds it 'wonderful' when Killua threatens her with his own life, so there's no point talking about her.) In assassination, he appears to be a bloodless, tearless killing machine and was brainwashed and trained to be so. However, unlike other Zoldycks, he secretly wants to make friends his own age and deeply values those around him, possessing the heart of a typical child who likes snacks and games. Even before learning Nen, he possessed enough physical strength to open a 16-ton gate. In other words, he transcended the level of an ordinary human long ago. His physical characteristics include a unique constitution immune to all poisons. This includes lethal toxins as well as various substances like laxatives. Because he is accustomed to all kinds of torture, he endures significant pain well, and his combat effectiveness does not decrease due to pain. By manipulating his own body, he attacks by slashing opponents with long, sharp claws that cut better than knives. This is a secret technique passed down in the Zoldyck family, separate from Nen abilities. He hates Illumi, who is the most obsessively fixated on him among the family.