Chairman of academy Kouyou, Genetic engineer from that institution who takes part in their research. She is also know to be the 《Blaze Diabolica》 because of her grandfather's name 《Blaze Innovator》. She also inherit her grandfather's research about the Lucifer.
Base on Tooru's first impression, she posses such "Devilish, or ominous" aura while watching him at first volume. And the time he tells how he thinks how heartless she could be to throw weak just like that but also he says he thinks he is wrong about it when the time Sakuya bow down and apologizing because she did not tell about the people in the island. But Sakuya didn't deny the fact she is heartless to throw others away if necessary for her own research and treating like them as experiments.
She seems to be quite calm but sadistic at both ways. But as her age she can't hide her dissatisfaction when Lilith Bristol whisper to Tooru ( that reach the chairman's ear ) that she truly shy and lie about herself. ( That proves to be a little lie of Lilith to make Tooru think Sakuya is a good girl.)
