AD 1999, Earth faced a dire crisis as the planet Lar Metal drew near. Yukino Yayoi learned of Lar Metal from Dr. Amamori at the Tokyo Observatory. Though a junior‑high teacher, she also assisted Dr. Amamori, whose work valued her stellar expertise. In truth, Yayoi was Queen Millennia, who had arrived from Lar Metal a millennium earlier and had observed humanity ever since. The ancient queen kept her identity hidden, guiding generations from the shadows of history.
Soon countless meteors struck Earth, plunging people into terror. During this disaster, Hajime—Yayoi"s pupil—offered his aid. Yayoi welcomed him into a vast subterranean cavern, where ancient relics glowed faintly in the dim light below.