Alluka Zoldyck

Alluka Zoldyck is the fourth child of Silva and Kikyo Zoldyck and Killua's younger sister. She shares her body with an entity called Nanika.

Alluka has long black hair, blue eyes and a pale complexion. She wears the traditional clothes of a Japanese shrine maiden with boots and a headband decorated with cartoon faces; matching faces adorn the bands holding the two locks of hair that frame her face.

Before she ever appears on screen, Silva describes his daughter as a dark and uncontrollable child, claiming that the circumstances of her birth left her without a soul and unable to feel. In Killua's company she is nothing of the sort — affectionate, simple and deeply trusting of him, most likely because he is the only person who has ever shown her compassion. She calls him "big brother".

In the Zoldyck family photograph she stands apart from the others, facing away — a detail that says a great deal about her place in that household.

Unlike her brothers, Alluka has no combat ability whatsoever; in strength and endurance she is an ordinary child. The danger her father fears has nothing to do with her and everything to do with Nanika. Voiced by Maaya Uchida.