Jinzaburou Matoba is a middle-aged man who serves as the director of the Far East Cultural Exchange Promotion Bureau, a government organization directly under the jurisdiction of the Japanese Cabinet. He has a neatly parted head of black hair that is showing some gray, and is of average height and build. His most distinguishing physical feature is his narrow eyes, which give him the perpetual appearance of smiling. He is typically dressed in understated suits, often in a leaf-brown color, which reinforces his discreet and professional demeanor.

Matoba's personality is a complex blend of laid-back affability and sharp, decisive pragmatism. He often speaks in a slow, relaxed cadence that contrasts with the typical image of an elite government bureaucrat, making him seem calm and approachable. However, this relaxed demeanor belies a sharp and calculating mind. When the situation demands, he does not hesitate to become firm and straightforward, making his opinions clearly known without evasion. He is a man who operates effectively in the shadows, preferring to manage affairs from behind the scenes rather than taking a leading role in the spotlight.

His primary motivation is to serve what he perceives to be the best interests of Japan. He is the mastermind behind the plan to subjugate the fantasy world of Eldant through a soft power cultural invasion, using otaku culture as a tool for economic and social monopolization. Matoba is a strategist who views the mission with cold, utilitarian logic, seeing the protagonist, Shinichi Kanou, as a disposable pawn perfectly suited for a potentially dangerous and deniable operation.

In the story, Matoba holds the central role of the liaison and project manager between the Japanese government and the operation in Eldant. He is the one who personally interviews and selects Shinichi Kanou in Akihabara, deceiving him with the cover story of a simple corporate job before having him kidnapped and transported to the other world. Throughout the series, he manages all the high-level negotiations, handles the vast amount of administrative paperwork for the Amutec corporation, and coordinates with both the Japanese government and the Eldant Empire, meaning he is rarely present at the mansion where Shinichi and the others live.

His most significant relationship is with Shinichi Kanou. Matoba acts as a distant mentor figure, watching Shinichi's progress from afar. He is responsible for many of the trials Shinichi faces, but also demonstrates a grudging respect for the young otaku's unconventional methods. When Shinichi discovers the true invasive nature of the mission, Matoba coldly lays out the facts, cruelly explaining that Shinichi was chosen because he was a person who could disappear from the world without anyone noticing. Despite this, this relationship evolves. When Shinichi proposes a more equitable and sustainable path forward, Matoba ultimately sides with him. In a key moment, he uses his skills to ambush his own superiors in an engineered public confession, recording their true aggressive motives and using it as blackmail to silence them and protect the new direction Shinichi has forged.

Matoba exhibits no special combat or supernatural powers, but his notable abilities lie entirely in the realm of strategy, politics, and administration. He is a master negotiator, a brilliant organizer, and an exceptionally skilled bureaucratic infighter. His most defining talent is his strategic vision and ability to identify and manipulate talent, as demonstrated by his recruitment of Shinichi. Throughout the series, he develops from a seemingly benevolent manager into a revealed antagonist and then into a powerful, if unlikely, ally. He begins with a perpetual smile, loses it when his perfect plan falls apart, and eventually finds a new way to proceed, regaining his smile while now aligned with Shinichi to make the cultural exchange a genuine success rather than a prelude to conquest.