He is Killua, Killua. The child of the famous killer family.
He is Sasuke, Uchiha Sasuke, the child who was sent on a road of revenge by his brother.
A time travel allowed Killua to become Naruto and Uchiha Sasuke, and met Uzumaki Naruto who was almost the same as Gon in every aspect.
Clear eyes, that kind of light that can light up everything even in the dark;
'Hey, Jay, I met you again...'