At the age of 17, Sonia set out to find her true purpose. She met Alucard, the prodigal son of Dracula, who was just beginning his own campaign against his father's madness. The two remained with one another for some time, and it is suggested that they fell in love. However, Sonia learned of the full extent of Dracula's evil from Alucard when he told her of his plan to fight his father, and after a time she left him to find her own way to the Dark Lord's castle.
Sonia met up with Alucard again inside of Dracula's Castle, and the two were equally astonished to see each other. Alucard did not want Sonia to be involved in the battle against his father because he feared for her life, and because he felt it was his own duty to deal with the transgressions of his bloodline. However, Sonia's determination to fight on was ferocious, and Alucard could tell that she would not back down. So to assure himself, he challenged her to a battle. Once she had pushed him to his limit, he conceded that her power was greater than he had known, and bid her a final farewell. He then entered what may have been the first of his long periods of sleep.
It is the year 1450, and the Dark Lord, Dracula, reached the height of his power, having undertaken a dark transmigration from his human body which gave him the power to rule over all that was evil. He began to send out armies of the undead to conquer the nations of the world one by one.