He is a member of "Metalborgs", the armed group born from the disfavor of "Dimensional Robos"' and the determination of protecting the nation in place of the latter. His aggressive form could frighten even robots born solely for the purpose of combat, but surprisingly, his original body was no heavy equipment. He had been a "lawn mower".
He was totally unrelated to "Metalworkers", the ex-Metalborgs. His current form was merely a result of a mishap when he went to a repair shop to fix his worn body. At that time, repair shops of all the place were busy with the remodeling of robots' bodies into Metalborgs, and he was mistaken as one of the Metalworkers to have his body customized for combat uses.
Though he was somehow forced to become a member of "Metalborgs", he works hard to fulfill his tasks with his new body now, and he quite likes his new body.
He is a silent man who focuses on his jobs. He doesn't get enraged easily. The only situations that fill his eyes with wrath are "when someone disturbs his work" and "when someone ruins his place of work"---and his place of work is, after all, the streets where people reside peacefully.