Eudoxia is a female vampire, older than Marius, who considers Constantinople to be her territory. She knows also that Marius possesses the King and Queen. She summons Marius, Avicus, and Mael to her home to tell them her story. Then, she threatened their lives if they did not give her the Royal Pair. Marius managed to make their escape, and went to Akasha to ask whether she wanted to be with him or under the watch of Eudoxia, who really just wanted the Queen's blood all to herself. Akasha made her will known to Marius, that she was going to protect him. Eudoxia came to the home that Marius shared with the other two, asking to see the Queen. Marius gave in to this wish and led her down to the shrine, where Eudoxia approached the Queen and asked her to be her victim. Akasha agreed to the sacrifice by grabbing her and draining her. But Marius, horrified by all of this, begged Akasha to spare her life. Akasha had taken Eudoxia as her sacrifice to answer Marius' question, that she was in his care and wished to be with no one else. Marius had thought, because he saved Eudoxia's life, that the malice between them was over. But it wasn't. Eudoxia killed a mortal in his home, and later on a band of angry mortals came to tear down his house, as they knew that their friend had been killed under the roof. Marius' house was destroyed. In a rage, he went to Eudoxia and dragged her to the shrine. Though she was older, he was clearly more powerful. Throwing her to Akasha, Marius watched as Akasha drained Eudoxia and then burnt her. Marius then knelt and cleaned the ashes up with his cloak, before sinking in the corner to cry. Marius had hope for Eudoxia when they met, thinking that they could form some sort of a bond. Unfortunately, he found such thing to be impossible, which broke his heart.
Santino and Marius met in the 1400's, as Marius stole out of the Sistine Chapel after discovering the enchanting works of Sandro Botticelli. He was entranced by the beauty of what he had seen, and Santino represented the total opposite of what Marius had found inside of the chapel. Santino, having heard tales of the powerful Marius, wanted Marius to come and join his satanic league of vampires that believed they served God by serving Satan. Marius was horrified to hear this, completely repulsed by the idea of joining Santino underneath the cemetery to reign over the minions and their chambers of skulls. He refused, and Santino accused him of being a heretic. Marius disregarded him, setting a small fire to his robes and knocking him down the steps to get him away. Santino was enraged. Marius had an after thought before sinking in to sleep that night, that he should have killed Santino. This would have been the wise thing. Months later, Marius' happiness was shattered when Santino gathered his satanic coven together to kill Marius. They burnt Marius badly, killed Vincenzo, kidnapped Amadeo and all of his other boys (all of whom they burnt to death during a ceremony). But luckily for Marius, he had his final revenge five hundred years later.