After the event that caused Captain Napolipolita's ship to perch atop Graviton City, three weeks pass and A-Ko and her friends embark on their summer break. A-Ko contemplates slimming down while B-Ko concocts a fresh scheme to topple her fiery-haired competition for the affections of C-Ko. Napolipolita and Spy-D lament their homesickness, yearning for a way back to their native planet. Meanwhile, Hikari Daitokuji, B-Ko's dad and the CEO of Daitokuji Financial Group, equips the local military with advanced mecha to attack Napolipolita's vessel and claim its cutting-edge technology.