Shortly after the conclusion (and success) of the first few controlled tests of the Katsura unit, the JSDF decided to continue with the planned ‘Mecha-Gina’ project (constructing fully functioning, human-sized mecha based on each of the three Mechagodzilla-type mechas) with a design based on the 1993-produced Mechagodzilla. Sheer, brute force was the key to this design, the built-in, self-sustained powerplant providing twice the capacity of the ones used in the Katsura and Jetta units simply to power the mecha-girl’s massive arsenal of energy weapons.

Even though the Katsura unit had failed in her first true mission, the JSDF had deemed it paramount to retrieve the mecha in order to repair and upgrade her. This became the primary objective of the Sumegi unit’s first mission; she was to make her way through the Daikaiju High complex and locate the machine (which had been taken by the k-girls after her deactivation to be studied and/or used in ‘sensuous activities’), eliminating any and all resistance in the process. In fact, this mission was an almost total success; the suddenness and feriocity of Sumegi’s initial barrage sending any nearby creatures hurtling for cover as she blasted her way through walls and rooms in order to acquire her target. However, just as she was about to leave with the Katsura unit, Sumegi was faced by Gina and Rhoda-Anne, and in the ensuing battle (which leveled still more of DKH) Sumegi was almost victorious, but an energy transfer between Rhoda and Gina allowed the later to blast apart a significant portion of Sumegi’s body, prompting a hasty retreat as to achieve her main objective of rescuing the Katsura unit.

Along with her ‘elder sisters’ (for some reason, the human AI within Sumegi is younger/less mature than that of Kiryuu, who is technically younger than her, leaving her to be counted as the youngest ‘sister’) Sumegi was transferred to DKH after the Mecha-Gina project was closed down, both as a student and as a security officer, though whether or not either of the three mechas take this job very seriously is debatable. She has found a friend in Musume, who followed the fight between Sumegi, Rhoda and Gina, already then seeing glimpses of Sumegi’s playful, childish personality.