Goro Otaki, widely known as Mr. O, is the elderly founder and director of Chiba, Japan’s Otaki Factory—an electronics shop and robotics workshop. A world-renowned scientist holding numerous international patents, his significant engineering contributions fund his deeper mission: protecting Earth from emerging threats, fueled by his fascination with UFOs, unidentified creatures, and paranormal phenomena.

Under Otaki’s leadership, Otaki Factory designs the mecha Jet Jaguar as a kaiju defense. He personally pilots it in early battles, like confronting Rodan at a summer festival, delivering theatrical Shakespearean monologues mid-combat. This engagement injures Otaki and damages Jet Jaguar, forcing a shift to autonomous control via AI systems engineered by his protégé, Yun Arikawa. Otaki finances the operation through patents and commercial robotics, enabling continuous upgrades to Jet Jaguar as threats escalate. Enhancements include replacing bipedal legs with wheeled tripods for mobility and integrating weapons like the Anguirus Spear, forged from a defeated kaiju’s spike, to combat kaiju such as Anguirus and Kumonga swarms.

Otaki demonstrates hands-on commitment during crises, joining his team in Tokyo’s final stand against Godzilla Ultima. There, Jet Jaguar activates an "invincibility" protocol, fusing the AIs Yung and Pelops II into Jet Jaguar PP. The evolved mecha sacrifices itself to trigger the Orthogonal Diagonalizer, erasing both Godzilla and itself to avert global Catastrophe.

Intellectually brilliant yet eccentric, Otaki exhibits a Cloud Cuckoolander demeanor, obsessively theorizing about extraterrestrial threats—partially validated by the interdimensional kaiju. His paternal leadership earns him the nickname "Pops" from Yun. He integrates cultural elements like kabuki poses and Buddhist prayers into operations. Despite his quirks, his foresight in preparing defenses and willingness to risk his life underscore his unwavering dedication as Earth’s protector.