Jingo Negoro, the 32nd head of the deeply entrenched Negoro family lineage, serves as grandfather to Botan Negoro. He oversaw her intense ninja training from childhood, rigorously preparing her for future espionage duties – a harsh regimen that led the young Botan to question his methods and sanity.

His past involves direct dealings with Nikola Tesla, who personally entrusted Jingo with safeguarding dangerous inventions known as Tesla Fragments. This critical responsibility defined the Negoro family's mission to prevent global threats posed by these artifacts, with Jingo's own legendary exploits forming a cornerstone of their legacy. His actions position him as a figure whose historical significance parallels the central narrative.

Physically, Jingo is a 96-year-old Japanese male with grey hair. He holds the title of chairperson emeritus within the Japan Safety and Promotion Company (JSPC), reflecting his esteemed, though retired, status. His legacy endures through Botan, whom he groomed to inherit the vital duty of protecting Tesla's inventions and combat organizations seeking their misuse.