Teppei Sugo was born on May 22, 2090, in Bunkyō, Tokyo. He graduated from Tokyo Metropolitan Nakano High School's Faculty of Information Engineering in March 2111. That same April, he joined the Ministry of Defense, assigned to the Navy Drones Unit of the National Borders Defense System. By November 2112, he transferred to the Drones Development Division. During the 2112 Operation Foot Stamp, Sugo unknowingly delivered VX gas, a chemical weapon, resulting in the deaths of his entire ground squad, including close friend Itsuki Otomo. This incident caused severe psychological trauma, clouding his Psycho-Pass and prompting his resignation in May 2113. He was confined at the Adachi Municipal Psycho-Pass Correction and Medical Care Center until release in November 2113. In December 2113, Sugo joined the Criminal Investigation Department's Division 02 as an Enforcer. Early assignments involved collaboration with Inspector Risa Aoyanagi and veteran Enforcer Tomomi Masaoka on drone-related terrorism investigations. Masaoka initially suspected Sugo but later developed mutual respect, encouraging him to pursue law enforcement if therapy failed. Tragically, during an operation at a therapeutic clinic, Sugo accidentally shot and killed Aoyanagi while attempting to neutralize a high-threat target. This intensified his guilt-driven tendency for self-sacrifice, exemplified when he shielded colleagues from an explosion set by terrorist Akira Kitazawa. Sugo transferred to Division 01 in November 2014. Physically, he stands 180 cm tall with a muscular build, excels in karate and soccer, and maintains a rigorous training regimen. Personal details include a preference for katsu-don, meditation as a hobby, and admiration for author Shiba Ryoutarou's work "Cloud Over the Slope." His motto is "Indomitable perseverance." By 2118, Sugo transitioned to the Ministry of Foreign Affairs Operations Department as a Special Investigator. In this role, he partnered with former Division 01 Inspector Nobuchika Ginoza. Their professional relationship evolved from initial tension following Aoyanagi's death to mutual reliance, notably during missions where Sugo provided critical support using specialized weaponry like the Assault Dominator. He continued demonstrating protective instincts, such as shielding Ginoza during high-risk operations. Sugo's military background and drone expertise remained assets throughout his career. Lingering guilt over past failures manifested in a disregard for personal safety, though this also fueled his dedication to protecting others. By 2120, he was active in the Foreign Affairs Operations Department's Suppressing Action Division, utilizing his combat and tactical skills in international operations.