Lucius Satan is the father of both Shirou Fujimura-Satan and Relia Satan as well as the widowed husband and lover of Miyako Fujimura. He is also the supposed killer of Miyako Fujimura and the ultimate cause behind Shirou's incredible fear of death. Despite being able to be characterized as an "Anti-Villain", he is a major antagonist to Shirou in Vanishing Dragon of Leviathan.