『Kaguya Sumeragi』

Age: 14-15

Height: 156 cm (5'1")

Kaguya Sumeragi is the young head mistress of the Kyōto House, and a supporter of the Black Knights. She is the representative of Sumeragi Concern, a large conglomerate founded by the Sumeragi House.

Despite her age and physique, she possesses a strong will and is highly influential amongst the Houses. Kaguya has admired Zero since his debut, and wishes to have his hand in marriage. Nothing anyone says contrary to this desire seems to faze her, including the suggestion that Zero might be sleeping with other women, to which she responds "A true hero enjoys physical pleasures," and proceeds to suggest that she, Kallen, and C.C. are Zero's harem.

Kaguya met Lelouch and Nunnally during their childhood at the Kururugi Shrine, and is Suzaku's cousin. She is the only living member of the Kyōto House following the Black Rebellion, having managed to escape to the Chinese Federation until Zero's return one year later. With the execution of Kirihara and the other members of Kyōto House, Kaguya states that she and Suzaku are the only remaining members left of the six clans of Kyoto.

With the formation of the United Federation of Nations, she is made the Supreme Council Chairwoman and the representative of the United State of Japan.

She is named after Kaguya, the main character of what is considered to be the oldest Japanese folktale.