Johness

Johness is a sadistic and psychotic individual, nothing gave him greater pleasure than the feel of bleeding flesh in his hands and hearing the screams of agony from his victims.

Johness is commonly known by his epithet "Johness the Dissector" before his sentence in Trick Tower, the single worst mass murderer in Zaban City's history. His murder technique was characterized by the plucking of flesh from the bone with only his bare hands as weapons. He was responsible for the killing of 146 people, all of which were severely dismembered to the point where none of their bodies were left in less than 50 separate pieces. He ended up receiving a 968 year prison sentence.

(Source: Hunter x Hunter Wikia)