In the world of Aramairu Continent, a fox-eared girl named Foxy serves as the commander of the Nanayon Company, a small band of tank mercenaries who operate a modified Type 74 tank. Despite their reputation as skilled warriors, with the panther-eared Kaffe as driver and the micro-dwarf Mimi as loader and chief mechanic, the company is perpetually broke and operating on a hand-to-mouth basis. Foxy's driving goal is to escape this cycle of poverty.

The story begins when Foxy rescues a young girl named Leona from slavers during a caravan stop. Leona possesses valuable information about a legendary gold plate that could bring immense wealth, and she also has sharp business acumen. As thanks for her rescue, Leona invites Foxy and her crew to join her caravan. Their journey is suddenly interrupted when a rival mercenary group attacks and annihilates the caravan, killing Leona's companions. Burning for revenge, Leona realizes she cannot match her enemies with military force and instead decides to destroy them using financial warfare, setting the stage for an intense money battle on the commodity exchange.

A notable narrative arc involves the disappearance of Foxy's mentor, an older man who trained her and who may have been a person transported from modern Japan. His departure early in the story leaves Foxy and her two remaining crew members to fend for themselves, forcing them to grow beyond his shadow. The narrative is characterized by a harsh and violent world where death is common and life is cheap, creating a grim atmosphere reminiscent of a western or a post-apocalyptic drama, a stark contrast to lighter tank-focused series.