In this game, a magical gate has been opened connecting the human world and demon world. Low-class demons have started appearing in the human world due to the dimensional overlap. You play as a character who must train and discipline these demons during a 30-day summer vacation. As demons have different common sense from humans, they will act strangely without guidance. If left untrained in human world rules and customs, the demons' influence could strengthen the magical gate and cause further issues. It is up to you to ensure the demons can peacefully live in the human world by the time the gate automatically closes in a month. You have the duty of training and looking after the demon citizens, teaching them appropriate behavior so they don't endanger themselves or other humans. [Translated from Japanese Wikipedia]