In the heart of the forest dwells Allen, an antagonistic sorcerer who is infamous as the "Demon Lord." His reputation precedes him, instilling fear in those who cross his path. One day, while living a solitary life as a hermit, he encounters Charlotte, a young girl who has collapsed in the woods. Despite being innocent, she was falsely accused of wickedness and had her betrothal annulled, forcing her to flee her homeland.
Upon hearing about Charlotte's plight, Allen is reminded of his own past suffering at the hands of those he once considered friends. Moved by her story, he decides to take her under his wing and teach her all sorts of nefarious deeds. With this newfound purpose, Allen welcomes Charlotte into his mansion and begins her tutelage in the dark arts.