"Battle Can Can" is a science fiction anime series set in a futuristic world where humanity has colonized space, and advanced technology has become an integral part of daily life. The story centers on a group of elite pilots known as "Can Can Fighters," who operate highly advanced mechs called "Can Cans" to protect their colonies from external threats. These mechs are unique in their design, combining sleek, humanoid forms with powerful weaponry and energy-based combat systems.

The narrative begins with the sudden appearance of a mysterious alien force known as the "Voidlings," which begins attacking human colonies across the galaxy. The Voidlings are enigmatic entities with unknown origins, and their attacks are both relentless and unpredictable. In response, the United Galactic Defense Force (UGDF) deploys its Can Can Fighters to counter the threat. Among these fighters is the protagonist, a young and talented pilot named Akira Tendo, who possesses exceptional combat skills but struggles with the emotional weight of past failures.

Akira is joined by a diverse team of pilots, each with their own motivations and backstories. These include Rei Nakamura, a stoic and disciplined veteran; Haruto Saito, a brash and impulsive rookie with a knack for improvisation; and Yuna Fujimoto, a brilliant engineer who provides technical support and develops upgrades for the Can Cans. Together, they form a cohesive unit, though their differing personalities often lead to tension and conflict.

As the series progresses, the Can Can Fighters uncover deeper mysteries surrounding the Voidlings, including their connection to ancient human technology and a long-forgotten war that once threatened the galaxy. The pilots must navigate political intrigue within the UGDF, as well as personal challenges, while striving to protect humanity from annihilation. Key plot points include the discovery of a hidden Voidling hive, the revelation of a traitor within the UGDF, and the development of a superweapon capable of turning the tide of the war.

The series balances intense mech battles with character-driven drama, exploring themes of sacrifice, loyalty, and the consequences of technological advancement. The Can Can Fighters' journey is marked by both triumphs and losses, as they confront not only the external threat of the Voidlings but also their own inner demons. The story culminates in a climactic battle that tests the limits of their abilities and resolve, ultimately shaping the fate of humanity in the galaxy.