One main theme could be the struggle between light and dark, as Vanitas is a character associated with the dark side. Another might be identity, since he has a complex origin.
The 'Kingdom Hearts Vanitas Novel' likely delves deep into the character of Vanitas in the Kingdom Hearts universe. It might explore his backstory, his connection to other characters like Ventus, and his role in the overarching plot of the Kingdom Hearts series.
One popular theme is redemption. The OC might be the catalyst for Vanitas to seek some form of redemption. Since Vanitas has a rather tragic backstory, the OC could show him a different path, a way to break free from his dark destiny.
In Kingdom Hearts fanfiction, the relationship between Vanitas and an OC (Original Character) can be really complex. It might start with conflict as Vanitas is often a rather dark and brooding character. The OC could be initially drawn into his world by accident or perhaps be a part of some grander scheme. For example, the OC might have a special power that Vanitas wants to either use or destroy.
One good one could be 'The Bond Beyond Darkness'. It really delves into the complex relationship between Ventus and Vanitas. It shows how their connection is more than just their opposing natures.
In a fanfiction, when Sora meets Vanitas, there could be an intense battle. Sora, being the heroic and positive - minded character, might initially try to reason with Vanitas. But Vanitas, with his dark and brooding nature, may not be so receptive. Their encounter could also lead to some revelations about the nature of darkness in the Kingdom Hearts universe.
Perhaps a fanfiction where Ventus has a premonition of a great danger that only he and Vanitas can prevent together. As they journey to stop it, they gradually form an unexpected bond. They learn that their connection is deeper than they initially thought, and this realization changes their relationship throughout the story.
One way to develop their relationship uniquely is to have a magical object that links their minds. This would mean that they constantly share thoughts and feelings, whether they like it or not. At first, they fight against this connection, but as time goes on, they learn to use it to their advantage and it deepens their relationship. For example, Ventus might use it to reach out to Vanitas when he is in danger, and Vanitas might start to rely on Ventus's positive emotions to fight against his own darkness.
Sora is known for his selflessness and his eagerness to help others. Vanitas, in contrast, is self - centered and often only concerned with his own power. When they meet in a fanfiction, Sora's friendly and warm personality clashes with Vanitas' cold and calculating one. Sora might try to reach out to Vanitas, but Vanitas may see this as a sign of weakness and try to take advantage of Sora.