TV-Series
Description
Henrietta de Tristain ascends to the throne of Tristain as crown princess following her father's death under unclear circumstances, sparking a palace power struggle. As queen, her concern for commoners and preference for diplomacy over military action endears her to her people despite the heavy burdens of rule. She possesses short purple hair, teal blue eyes, and stands 158 cm tall. Her typical attire includes a purple cloak, a white silk long-sleeved dress, white stockings, high-heeled shoes, and a diadem or crown, with measurements of 84-59-85.

She shares a close childhood bond with Louise de la Vallière, later formalized as adoptive sisters after Louise renounces her noble status, making Louise second in line to the throne. Royal duties and Louise's deference to her as sovereign rather than friend strain this central relationship. Henrietta harbored deep romantic feelings for her cousin, Prince Wales of Albion, vowing eternal love even after his assassination. His dying wish for her to find happiness with another initially proved difficult.

Her character evolves as she develops feelings for Saito Hiraga, Louise's familiar. Envying Louise's resolve, Henrietta confesses her love to Saito while disguised at the Slepnir ball, causing tension when Louise discovers them. Later, a magical mirror relic in her bedchamber transports her to a hidden room in Saito's mansion. There, they share a kiss during a private discussion about political pressures, including her impending marriage for state stability. Though she proposes further clandestine meetings, Saito declines out of loyalty to Louise. These incidents cause Louise to flee temporarily; Henrietta assists the search and resolves not to interfere in their relationship, despite intermittent wavering.

As queen, she navigates major crises, including an Albion invasion after Wales' death. She demonstrates leadership in battles, mobilizing allies against an Ancient Dragon threatening Tristain, achieving victory with elvish aid. She later attends Saito and Louise's wedding. In statecraft, she cancels her own wedding in Vindobona and gifts Prince Wales' ring to Tiffania Westwood, recognizing her as Albion's last royal survivor. Henrietta rarely employs her hereditary water magic, though combined with Wales' power she can achieve hexagon-level spells.

Her personal interests include disguising herself, dancing to "Fairy's Lunch," and consuming horn-sheep soup. She has a competitive history with Louise, tallying 29 wins, 24 losses, and one tie. She values freedom, stating, "Freedom is the best treasure, after all." In the anime adaptation, she explicitly states she will not abandon her love for Saito, hinting at a potential polygamous arrangement common among nobles.