Maō is the ruling Demon Queen of the demon realm and the forty-third Demon King, a title that is a formal designation rather than a personal name. She belongs to a clan of demons known as the library clan, a group that prioritizes knowledge and closely resembles humans in appearance. Despite her youthful appearance, she is several centuries old. She possesses a gentle and peace-loving nature and is a committed pacifist who seeks to end the long war between humans and demons. Her primary motivation is to move beyond the cycle of conflict and create a stable, prosperous future for both races, a goal she refers to as reaching the other side of the hill. She understands that simply defeating the human hero would not solve the underlying problems, as the war has become economically and politically entrenched in both societies. When the Hero finally reaches her castle intending to slay her, she instead proposes a partnership and convinces him that a sudden end to the war could lead to even greater chaos and suffering. She persuades him to work with her to achieve lasting peace. In human society, she disguises herself as a human noblewoman called the Crimson Scholar. Under this alias, she shares her vast knowledge of economics, agriculture, technology, and governance to gradually reform human society from within. She is highly intelligent and knowledgeable, with access to a vast repository of information known as the outer library, which grants her understanding of advanced concepts. Her relationship with the Hero is the central partnership of the story, evolving from adversaries into close allies and later into a romantic bond as they work together. She also develops relationships with other key figures, including her loyal maids and the various students she mentors. Throughout the story, she faces numerous challenges, including political opposition from conservative human factions, the machinations of warmongering demon clans, and even the influence of past Demon Kings. She grows as a leader, learning to navigate complex political landscapes and defend her vision against those who seek to maintain the status quo. Her notable abilities are not based on raw combat strength, but on her exceptional intellect, her strategic and economic expertise, her access to advanced knowledge from the outer library, and her persuasive diplomacy. She wears decorative horns as an accessory, and her distinctive red hair and eyes have earned her the alias of the Crimson Scholar.