Silva is Killua's father. He is a silent, pensive figure, and Killua seems to rarely interact with him, although Killua does look up to him. He allows Killua to go along with Gon on their journey, but this is only so Killua would gain more experience when thrown out into the real world on his own. In fact, Silva was confident that Killua would eventually return home on his own, as an assassin.