Lucci is one of five foremen at Galley-La Companys Dock One and has a unique way of communicating through his pet pigeon, Hattori. Despite not being able to speak, Hattori displays impressive skills in fights against Paulie and Luffy. Not much information is available about the significance of Hattori or why he acts as Luccis voice. When acting as Lucci's voice, Hattori exhibits human-like body language and insults Paulie for his reckless lifestyle. It seems that Hattori has a special bond with his emotionless and bloodthirsty master. He flies to Luccis unconscious body and leaves him when he enters any battle, only returning after the fight is over. The name "Hattori" likely comes from combining the Japanese words for pigeon (hato) and bird (tori).
Even at the tender age of thirteen, Lucci was already known to be a very capable mass-murderer, having killed 500 soldiers and a crew of pirates single-handedly. It should be also noted that Rob Lucci is the strongest member of CP9 in history by far.Lucci ate the Neko-Neko no Mi, Model: Leopard, a Zoan-class Devil Fruit which allows him to transform into a leopard and a giant leopard-human hybrid.
Lucci is later revealed to be a member of CP9, more properly known as Cipher Pol Number 9, and one of the main antagonists of the Water 7 and Enies Lobby Arcs. Lucci comes off as a cold and collected CP9 agent, almost never displaying any emotions. In spite of his seeming lack of emotions, he does not like being insulted. During his fight with Luffy he did not pay attention to Usopp, until he started to insult him.
An example is the brutal assault on his friend of five years, Paulie, whom he even tried to kill after the CP9's identities had been revealed. He also states that he feels no true bond with the city he's lived in for five years, and he seems to have no feelings for his fellow CP9 colleagues, least of all Spandam.As the strongest member of CP9, Rob Lucci's great power is acknowledged even by the Shichibukai.