Dokurobei is the enigmatic mastermind and primary antagonist who leads the Doronbo Gang from the shadows in their quest for the Dokuro Stone. He is a self-proclaimed god of thieves, though his true nature and origins are far more complex than this title suggests.

His background is that of an alien visitor from the Dokuro planet, also known as Planet XYZ in later media. He arrived on Earth when the planet was still a ball of molten magma, and the extreme heat caused his body to shatter into four separate pieces. After spending eons in this fragmented state, he devised the legend of the Dokuro Stone, claiming it was a family heirloom that contained a map to a vast fortune of gold. In reality, reassembling the stone was the only way to restore his own physical form and allow him to return to his home world.

Throughout most of the original series, Dokurobei remains a mysterious, unseen figure. He communicates with the Doronbo Gang through various disguised robots or devices, which often masquerade as food or everyday objects. After delivering his instructions on where to search for a fragment of the Dokuro Stone, these communication devices typically explode, much to the gang’s dismay. He has a distinct verbal tic, often adding the sound "beh" to the end of his sentences, and he is known to shout "Akapontan," a term meaning idiot or nitwit, at the trio when they fail him. His personality is characterized by a massive ego, a short temper, and a self-centered nature. He is quick to punish his subordinates for any sign of disobedience or failure, regardless of whether his own faulty information was partially to blame.

Dokurobei’s role in the story is that of the puppet master. He drives the plot forward by setting the Doronbo Gang on their treasure hunt, promising them half the fortune upon completion. His key relationships are exclusively with the three members of the Doronbo Gang: the leader Doronjo, the inventor Boyacky, and the strongman Tonzura. While he treats them as expendable pawns, punishing them comically after each defeat, it is also noted that he has a crush on Doronjo, a fact she occasionally tries to exploit.

The character undergoes a significant development and revelation in the finale of the original series. After the Doronbo Gang finally gathers all four pieces of the Dokuro Stone, his true appearance is revealed. The human-like form he sometimes used, a short, portly man with glasses and a large mustache, was just another decoy. His authentic form is the Dokuro Stone itself, a skull-shaped alien being. Once restored, he unceremoniously abandons the Doronbo Gang, leaving them with nothing but broken promises as he returns to his home planet.

In later iterations, particularly in Yatterman Night, Dokurobei is depicted in a much darker light. Having succeeded in returning home, he chooses to come back to Earth for revenge against the Yatterman team who foiled his plans. In this version, he defeats the original heroes, shatters the moon, and establishes a tyrannical dictatorship under the false identity of Lord Yatterman. He enslaves the surviving human population, brainwashes individuals to serve as his generals, and drains the life force from people to maintain his own immortality. His motivations shift from a desire to simply return home to a cruel and totalitarian ambition to rule over Earth.

Regarding notable abilities, Dokurobei possesses genius-level intelligence and is a master of deception and manipulation. He can create incredibly lifelike robotic decoys of himself to conceal his true form. In his more powerful incarnations, he has demonstrated abilities such as telekinesis, electrokinesis, and the power to grow to a colossal size. His primary strength, however, lies in his ability to orchestrate schemes from a distance, using others as his instruments.