Killua is a boy who closely "observes" Gon Freeccs. Gon is typically boy who plays basketball, popular, and is seen to have an optimistic attitude. But just when Killua gets close to Gon, he realizes that his past and attitude are not what they seem.

"Wh-what do you want to know?" Gon asks, leaning back in his chair to stay away from him. "First of all, your age," Killua says, his smile fading. "I need to know if you're the legal age to..." "...to what?" Gon asks, and Killua shakes his head. "Never mind, just tell me." He answers, his smile returning. "Eighteen..." Gon says, and the silver-haired boy smiles. "Perfect!" Killua shouts, clapping his hands together. "The same age as me!" Gon smiles awkwardly at the boy. || The result of having two boys of opposite personality live together. [Killua Zoldyck x Gon Freecss]