In the not-too-distant future, humanity discovers a swarm of enormous, insectoid aliens traversing the galaxy. These extraterrestrials appear bent on wiping out the human race as it begins to venture beyond the solar system, and they draw steadily nearer to Earth. In response, mankind constructs interstellar warships and colossal mecha. These machines are operated by the most talented and promising young people on Earth, selected from training academies across the globe. The narrative starts in 2023, shortly after the initial skirmishes with the aliens, and focuses on the young Noriko Takaya. Though her father—a renowned space fleet captain—was killed in one of the war's early battles, Noriko's own piloting abilities are far from certain. Nevertheless, she enrolls in a training school. Throughout the series, Noriko, alongside the skilled and beautiful Kazumi Amano, strives to overcome the scars of conflict, the skepticism of her classmates, and her own deep-seated insecurities.

In this installment

Since the conflict with the Space Monsters erupted, many generations have come and gone, and few recall its origins—documentation from that time is sparse. Despite the bleak outlook, humanity persists in their struggle, depending on the "Topless," a distinguished corps of space pilots with unique talents allowing them to wield the Buster Machines, humanity’s last line of defense. Nono, a young woman hailing from a distant Martian village, has been captivated by tales of the famed pilot "Nono-Riri." Yearning to break free from her routine existence, she is determined to emulate her idol. Naively oblivious to the impending peril, she is unwavering in pursuit of her ambition. Fate intervenes when Nono meets Lal'C Melk Mark, a solitary Topless pilot, and she resolves to follow Lal'C into the unknown, regardless of the risks involved.