Alfin Reise Arnor (アルフィン・ライゼ・アルノール), also known as one of Erebonia's greatest treasures (帝国(ていこく)の至宝(しほう)), is the Princess of Erebonia and the twin sister of Crown Prince Cedric. She attends St. Astraia Girls' School, where she became friends with Elise Schwarzer. During the Erebonian Civil War, Alfin joined Class VII on the Courageous to express the imperial family's support.