Johan Deiter Rudiger  

, ヨハン・ディーター・リューディガー

A German student known as the Prussian Devil has gained worldwide recognition for being a skilled user of Beatrice. Despite a draw in battle against Ayako, it was Ayako who sustained serious injuries while Johan barely suffered scratches. Although Ayako demonstrated impressive fighting skills, Johan views her as his potential bride due to her worthiness and the fact that no one else compares to her, including Mamoru. In addition to his exceptional Beatrice control, Johan is also highly intelligent and currently collaborating with Ayakos uncle on a research expedition exploring the origins of Beatrice.