"Crane Game Girls Galaxy" is a short-form anime series that blends comedy, science fiction, and slice-of-life elements. The story revolves around three high school girls—Haruka, Ayaka, and Saki—who are unexpectedly recruited by a mysterious alien named Kuroneko to become Earth's defenders against an intergalactic threat. The trio is tasked with piloting giant mechs called "Galaxy Dolls," which are modeled after crane game prizes, to protect the planet from invading space forces.

The narrative begins with the girls leading ordinary lives until Kuroneko appears, claiming they have been chosen due to their unique compatibility with the Galaxy Dolls. Despite their initial reluctance and lack of experience, the girls are thrust into battles against bizarre alien adversaries. Each episode features a new challenge, often involving quirky and humorous scenarios, as the girls learn to work together and harness the abilities of their mechs. The series balances lighthearted comedy with moments of action, as the girls navigate their dual roles as students and intergalactic heroes.

Haruka, the protagonist, is energetic and determined but often impulsive, while Ayaka is more reserved and analytical, providing a counterbalance to Haruka's enthusiasm. Saki, the third member, is laid-back and carefree, often serving as comic relief. Kuroneko, the alien mentor, adds an eccentric dynamic with her cryptic instructions and unusual methods of training. The interactions between the characters drive much of the humor and charm of the series, as they grow into their roles as defenders of Earth.

The plot progresses episodically, with each installment focusing on a specific alien threat or personal challenge faced by the girls. Despite the episodic structure, there is an overarching narrative involving the origins of the Galaxy Dolls and the true nature of the alien invasion. The series maintains a light tone throughout, emphasizing the absurdity of its premise while delivering consistent comedic and action-packed moments. The combination of quirky characters, imaginative mech designs, and a playful approach to the sci-fi genre makes "Crane Game Girls Galaxy" a distinctive entry in the short-form anime category.