Gun Gun Pixies is an innovative third-person shooter that introduces players to the tiny yet powerful alien characters, Usamaeru and Kamerieru, who embark on an important mission to save their home planet, Pandemo. To accomplish this, they must infiltrate a college girls' dormitory on Earth to study human behavior. Armed with their unique weapons loaded with Happy Bullets, which have positive effects, players will engage in stealthy operations, gathering vital information while navigating a world that is hilariously oversized compared to the pixies.

The game presents a variety of gameplay experiences, including exploration, combat, and strategic objectives. Players will encounter three main stage types: Search & Combat, Pacification, and Bathing. Each stage offers its own challenges and requires keen observation of the girls' Sight and Listen gauges to avoid detection. Players can also utilize sniper vantage points throughout the levels for an added tactical edge.

As players progress, they can shop for new scopes, weapons, and costumes to enhance their pixies. With giant girls around every corner and quirky enemies like squids, Gun Gun Pixies promises a comical and action-packed adventure as you help the pixies repair social issues and learn about humanity.