Henrietta

Henrietta de Tristain (literally meaning, 'Henrietta of Tristain') is the princess. Her father died and there is some power struggle in the palace. Henrietta and Louise were childhood friends. She had to take over after her father died. It is unknown if her father died of natural causes, or if he was murdered. She is loved by people of Tristain and later becomes Queen of Tristain. She has to hold off a invasion from Albion after the assasination of the Albion prince.

Henrietta has three cousins we know of: Tabitha, Tiffania, and Wales. She and Wales were lovers, but he ends up being murdered. She has vowed to love Wales forever, even though his dying wish was that she would fall in love with another man. He simply wanted this so that she could be happy.

Later in the series, Henrietta seems to develop feelings towards Saito. At first, she doesn't even realize it.