To create an engaging Dracula OC fanfiction, research is key. Learn about the original Dracula story, its themes, and the setting. When creating your OC, think about how they fit into this world. Are they a new vampire in Dracula's lair? Or perhaps a human trying to resist his charm? Build tension in the story by creating conflicts between your OC and the existing Dracula lore characters.
Start with a strong concept for your OC. What makes them special? It could be a unique power or a moral code that sets them apart. In the fanfiction, introduce the OC gradually. Let the readers get to know them bit by bit. As for the Dracula aspect, play with the classic elements. You can rewrite the relationship between Dracula and your OC. Maybe your OC has a secret that Dracula is desperate to uncover, which can drive the plot forward.