Vergo (in Japanese: ヴェルゴ Verugo) was one of the top four executives of the Donquixote Pirates, and the secondary antagonist of the Punk Hazard Arc. Being a spy for Donflamingo, was given the task of assisting Caesar Clown. He disguised himself as a Navy officer, commander of Branch G-5. Using his rank, he was able to hide Caesar's operations of testing drugs on kids, telling those children's parents that they should forget about their children, saying they can never be found.
Vergo is a tall man with short black hair and sun glasses. He wears a white jacket over his navy shirt and white pants with yellow shoes. In some appearances he sometimes have piece of food stuck to his face. But most of the times, he maintains a stern look on his face.
Vergo is a relatively calm individual. He takes his jobs and missions seriously like watching over Caesar Clown. Despite his calm personality, Vergo is shown to be a cruel person by kidnapping children from an island and giving them to Caesar so that he can drug them. Vergo can sometimes lash out when people like Law disrespects him, such as not reffering to him by the right name. Vergo's shows great respect for his leader, Donquixote Doflamingo, and would do anything the he asks him to do. When he shows his true colors towards the G-5 Marines, Vergo is utterly ruthless, heartless and uncaring as he kills or brutally injures his former subordinates for no reason at all and believing that anything he does to them is his right, believing they are nothing but rejects.
Vergo is a skilled martial artist, and is proficient with the ability of Armament Haki, and is also shown to be very fast. His Armament Haki is so great, he's able to turn his entire body to iron. However, this power is still vulnerable to Trafalgar Law's Ope-Ope no Mi powers.
Vergo is also seen carrying a bamboo stick. He can put his Haki into the bamboo stick making it become much more durable and harder.
As a child, Vergo met Doflamingo and was there to witness the child murder his father. Later on, Vergo managed to join the Marines to spy on the activities of their activities and to warn Doflamingo of their plan.
On Minion Island, Vergo was there to secretly assist the Donquixote pirates on obtaining thw Ope Ope no Mi but managed to run into a young Law (who already ate the Ope Ope no Mi)who gave away incriminating evidence on Doflamingo. Law also wanted Vergo to help out his companion as well which was to Vergo's surprise Rosinante (Doflamingo's brother). Realizing now that Corazon was a spy and Law was his accomplice, he beat the two up and alerted Doflamingo about Rosinante's treachery. After Rosinante's death and Law's escape, Vergo along with the Marines and the Donquixote Pirates eventually left the island after fighting.
Punk Hazard Arc
Vergo first appears in a corridor along with Monet in Punk-Hazard when he crushed Trafalgar Law's heart. He berated Law for his incompetence and captured him. Once he was with Caesar Clown and Monet, Caesar Clown proceeded to unleash Shinokuni on the island to show the underworld what it is capable of. When the remaining Marines and Straw Hats made it to the safety of the laboratory, Vergo decided to head to Tashigi's location to eliminate them all.
He proceeds to attack Tashigi and the G-5 marines until he was confronted by Sanji. In their battle, Vergo got the upperhand and was about to land a powerful blow on the pirate before going to the SAD room. While on his way there, Vergo was giving instructions by Doflamingo to kill Law. Once he made it to the SAD room, Vergo immediately attacked Law. Before Vergo could finish off Law, Smoker intervened and decided to battle Vergo because of how the latter betrayed the marines. The two fought until Vergo defeated Smoker.
When Law got his heart back, Vergo now turned his attention to Law and fully intended to finish him off in his full body Armament Haki mode. But before Vergo could land one blow, Law bisected him and a portion of Punk Hazard. Now defeated and having parts of his body hanging on a steel railing, Law sets the SAD room to explode in couple of minutes. When Law and Smoker left, Doflamingo (through Vergo's den-den mushi) told Vergo that he will miss him and that he has a done a great job up until now. Afterwards, the SAD room exploded killing Vergo.