Height: 183 cm

Director of the Sponheim Abbey, he is a powerful Magus and a friend of Aozaki Touko and Araya Souren when the three studied at the London branch of the Mage's Association. Cornelius is a direct descendant of the Renaissance-era scholar and magus Cornelius Agrippa von Nettesheim. Contrary to his appearance—likened to "an agreeable youth in his twenties" in the novel—he is over fifty years old and has a cruel disposition.

He and Touko were on good terms when they were students until Touko surpassed him in their study of Runes. He is so obsessed with this inferiority complex that he occasionally becomes deranged when speaking of her. His sole purpose in aiding Araya is to kill Touko to prove his superiority.