Killua is a cheeky, laid back, mischievous 13-year-old. He is often skeptical and sometimes cynical. He can be quite rude and blunt to others, especially people who annoy him, his close friends, and people he deems unworthy of his respect. He has a sweet tooth. He is a quick thinker and often analyzes a situation well with ease. He is part of the Zoldyck family of assassins, and had a horrible and torturous upbringing he doesn't talk much about. He is loyal to his loved ones. He is very smart.