Aim for the Top2!

A girl named Nonno has run away from home and come to the city alone. She harbors a grand dream: to become a Space Pilot. However, reality falls short of her ambitions; since arriving in the city, she has been working part-time at a small restaurant near the spaceport every day. One day, when she is teased by regular customers, Ruruko, a "real" Topless (Space Pilot), who happens to be visiting the shop, steps in to rescue her. Deeply moved by this act, Nonno not only calls Ruruko "Big Sister" but also follows closely behind her, exclaiming, "I want to be a Space Pilot too!" Nonno is taken to the headquarters of the autonomous mutual-aid organization located on the satellite base "Giant Cloud." The handsome young Topless "Nikola" and the instructor "Casca" are highly curious about this girl's true identity and abilities. Meanwhile, the Mars Defense Force is deeply concerned by repeated attacks from Space Monsters on the ground. They summon Ruruko back to their ship for questioning, but unexpectedly, Commander Hatori, who has always despised Toplesses, ends up detaining Ruruko. Just then, new Space Monsters suddenly appear in the Martian region accompanied by gravitational tremors... Elite Topless members receive orders from their superiors to intercept the massive Space Monster fleet known as the "Jupiter Express." To support this operation, the newly built Buster Machine "Caveman" is deployed to the front lines. Since Chizuru lost her own Buster Machine in the previous battle, she views Nonno, who attempts to seize the pilot's seat, as a rival. One day, these two girls encounter a group of children who have a request for the Topless...