"Each of my victims' screams and facial expressions inspired my work."
Benny Delon (ベンニー゠ドロン, Ben'nī Doron) was a famous serial killer who lived about 100 years prior to the present day of Hunter × Hunter that the story takes place in. Due to his excellent forging skills, some would come to regard him as an artist.
Benny seemed to have been on the final stages of male pattern baldness, as a result, the hair on the top and the crown regions of his head was missing, while he grew the rest long. He also grew side-whiskers and a beard and had kept them short and well-trimmed. He was depicted as wearing suits.
Benny was a skilled blacksmith and a serial killer. Every time he killed someone he made a knife engraved with a number and called it Ben's. Probably unknown to himself and likely ignorant of the concept of Nen, he put aura (that has weakened over time or was originally weak) into his knives during their creation that persisted and could be detected by a Nen user via intuition or observed using Gyo. He sold the knives in his shop, like other normal knives and swords. A total of 288 Ben's knives were made. According to his statement while in prison, "Each of my victims' screams and facial expressions inspired my work." This would imply he had murdered at least 288 people prior to being caught. His artistic activity could be divided into at least three periods.
Yorknew City arc
Gon and Killua find one of Ben's knives in Bull Market in Yorknew City. Later, Chrollo Lucilfer is seen using a Ben's knife to cut Silva Zoldyck's left arm in retaliation during his combat with the assassin and the latter's senior.
Abilities & Powers
Benny was a skilled blacksmith whose works are recognized, valuable, and even achieved the status of art. He is also a prolific serial killer with at least 288 victims.
Benny can be considered a Nen genius since it is implied (by analogy with Zepile) that he uses Nen unconsciously to make his works more attractive or at least managed to put aura in them. It is not known if his residual aura gives some special property such as sharpness or durability to his knives.
The most likely explanation for his creations still having aura even long after his death is the "post-mortem Nen" phenomenon.
Translations around the World