In the bustling halls of a modern university, a determined young woman named Iijima steps into an unfamiliar era with a critical quest at hand. Having traveled from a future overrun by monstrous replinoid beings, she begins her search for someone capable of mastering an advanced weapon and standing against the looming catastrophe. Her focus remains fixed on safeguarding Earth's women from the horrors that await, setting events in motion that could reshape the fate of both timelines. As initial encounters unfold, the path to alliance and resistance starts to reveal itself.