According to a 2005 interview with the game's producer Koji Igarashi published in the official Konami strategy guide, he stated that the decision to set the game three years after the events of Castlevania III: Dracula's Curse was significantly driven by his love for the game. The introduction of the "Innocent Devil" system, where players have a demon servant fighting alongside them, prompted him to consider the game's placement within the Castlevania timeline. Given the demonic nature of the Innocent Devils, Igarashi decided the story should align closely with that theme.

The idea he came up with back then revolved around a hidden narrative during Ralph C. Belmont's battle against Dracula, where there existed someone who betrayed Dracula, and another individual who relentlessly pursued this traitor. Igarashi believed that despite these circumstances not being part of the officially recorded history in-universe, they still significantly impacted Dracula’s defeat, and in that sense the gameplay system came first and the story was woven around it,