The love between brother and sister. The love between man and woman. That which is most forbidden is most unyielding. The two sons and five daughters of the Shiunji family shine like brilliant gems, each with intelligence and beauty in equal measure. And with the pedigree of their wealthy father behind them, how could they not be the talk of the town? Eldest son Arata has spent his life being tossed around by the whims of his colorful sisters, yet a little teasing won't stop him from valuing his family over anything and anyone else. But when his youngest sister turns fifteen, their father reveals a long-hidden secret of the Shiunji "siblings" and knocks Arata's world off its axis...

Episodes based on Mikoto scenario.

Naoki Kuzumi, a junior in high school, had lost his parents in an accident five years ago, and is living with his aunt, uncle, and cousin Matsuri. He always thought his life was ordinary, besides the fact that he can't remember what happened in his youth. One sunny day as he is taking a nap on a bench, a redheaded girl -- Mikoto -- literally falls on him from the sky. For some reason, she thinks he's her younger brother. Naoki's time period is a temporal shelter for those in the future, when many are suffering from an incurable disease. When she heard her younger brother Yuusuke had been taken to Naoki's time, Mikoto herself had gone back in time.

Over a century ago, astral mages under persecution from the Empire banded together and established the Nebulis Sovereignty under three founding families: Lou, Hydra, and Zoa. With the leadership of Millavair Lou Nebulis VIII, the Sovereignty aims to minimize casualties in their conflict with the Empire—a stance the extremist Zoas disagree with. Tensions rise between the families as the upcoming election to decide the next leader approaches. The Zoas are willing to do anything to achieve success; however, a world-ending war may ensue should they be victorious. Princess Aliceliese "Alice" Lou Nebulis XI has no choice but to cooperate with any potential allies in order to advance towards her ultimate goal of ending the conflict that has long tormented everyone involved. This includes Iska—one of the Empire's greatest warriors and her greatest rival.