He is the son of one of the noble families of the Kingdom of Sphere. He was initially chosen to be Feena's fiancé, but she instead falls in love with Tatsuya. Unlike the princess, Jürgen hates the people of the Earth, thinking them to be inferior, and wants to re-start the war between the two worlds. He attempts a coup d'etat of the Royal Family, and in total desperation, tries to kill Feena. In the end, Tatsuya prevents the attempted assassination and Jürgen is arrested for treason.