In the distant future, warfare has undergone a transformation where "Objects" reign supreme as the primary tool of destruction on battlefields. These massive orb-like tanks possess impenetrable exteriors and devastating firepower, effectively rendering traditional armies obsolete. Nevertheless, a disruption to this futuristic warfare is imminent. Qwenthur Barbotage and Havia Winchell serve in the Legitimate Kingdom's 37th Mobile Maintenance Battalion, providing support for the Baby Magnum - an Object used in combat. During a failed battle, they find themselves facing an enemy Object, completely outnumbered and overpowered. In a fight for survival and to protect their fellow soldiers, a glimmer of hope appears that challenges the world's perception of Objects. The story of Heavy Object centers around the journeys of Qwenthur, Havia, and Baby Magnum's pilot, Milinda Brantini, as they navigate the globe and encounter one impossible situation after another, battling against insurmountable Object foes. Leading them into battle is their commanding officer, Frolaytia Capistrano, as they must utilize all their intelligence and bravery to come out on top.