Empress Tianzi

Tianzi (天子, Tenshi) is the young Empress of the Chinese Federation, thus far referred to only by the traditional title attributed to the Chinese Emperor (Tianzi literally means "the Son of Heaven"). She is a young white-haired girl of about six years in age.

In practice, she is effectively a prisoner within her own palace, which she dislikes. She rescued a young Li Xingke from execution for stealing some medicine, and in return he promised to take her outside the palace walls. In the second season, she befriends Kaguya Sumeragi during their talks concerning the future of Area 11.

She was to be married to Prince Odysseus in a political marriage in the second season, but the ceremony is interrupted by Li Xingke and the Black Knights, who instigate a coup d'état, murdering the High Eunuchs who were in control at the time, and placing her back in control of the Federation, making them Lelouch's first allies in his global alliance. She later became the representative of the newly formed United States of China, though she in presumably under direct control of the Black Knights.