Seventeen-year-old William Twining takes pride in his lineage as well as his devotion to modern science. When he learns that his family has gone bankrupt, the pompous noble is faced with the reality that he can no longer afford his tuition or the lifestyle he is accustomed to. In a desperate search for valuables in his manor, William discovers a hidden room and accidentally summons the arrogant demon Dantalion, the Grand Duke of Hell.