Aileen overcame all the difficulties and got engaged with Claude. Just when she thought she found her happily ever after, she receives news that a demon named Ashtarte attacked a human village in the Mirchetta region. Sensing new dangers, Aileen infiltrates Mische Academy in the Grand Duchy of Mirchetta to investigate the situation. There, she meets James Charles, the last boss of Regalia of Saints, Demons, and Maidens 2 as well as the other quirky members of the student council.
The prodigal son of the 
Grand Duke of Mirchetta
كان ابن دوق ميرتشيتا الضال
Sembra che il figlio dissoluto 
del granduca di Mirchetta
O filho pródigo do
Grão-Duque de Mirchetta
непутёвый сын герцога Мирчетты