One common theme is the exploration of their contrasting personalities. Cinder is often seen as more mysterious and brooding, while Ruby is more cheerful and impulsive. Fanfictions like to play with how these two different personalities interact and complement each other.
One common theme is redemption. Maybe Cinder, who is often seen as a villain, is on a path to redemption because of Ruby. Another theme could be the power of friendship or a strange connection that defies their opposing natures.
One common theme is the exploration of the relationship between good and evil. Ruby represents the good side, and Cinder is often seen as the antagonist. Their relationship in fanfictions might explore how they can influence each other's views on this dichotomy.
Another theme is the exploration of the unknown. Vampires are often associated with mystery, and when combined with the already complex characters of Ruby and Cinder from RWBY, it creates a situation where the characters are forced to explore new aspects of their world and themselves. For example, Ruby might have to face her fears of the supernatural, while Cinder could be using the vampires for her own gain in a world she doesn't fully understand yet.
A common theme is friendship. Since they are from different backgrounds, their journey to become friends is often explored. Another is redemption. Cinder might be a character with a troubled past, and Ruby can be the catalyst for her change.
One common theme is redemption. Cinder is often portrayed as a character who might find redemption through her interactions with Ruby. Another theme is the power of understanding, as they come from very different sides in the RWBY world.
The exploration of their backstories together is also a theme. Writers may create scenarios where Ruby and Cinder's pasts are somehow intertwined, perhaps revealing secrets that change their relationship in the RWBY universe.
Redemption is also a popular theme. Since Cinder is a villain, many fanfics like to see if she can be redeemed, often with Ruby playing a key role in that process. For example, Ruby's kind nature might inspire Cinder to change.
Perhaps the fanfiction could be about Cinder Fall being sent back in time to a point before she became evil and meeting Ruby as a child. Ruby's kindness towards Cinder at this early stage has a profound impact on her. As Cinder grows up, she constantly struggles between her original dark destiny and the new path that Ruby's friendship has opened up for her. This internal conflict could be the central theme of the story.
The theme of redemption also appears. Cinder, with her past actions and the way she was treated, often finds redemption through her relationship with Kai. He helps her to see that she can be more than her past mistakes and that she has the potential to be a great force for good in their world.
One interesting concept could be the exploration of their opposing natures. Ruby is often seen as pure - hearted and full of hope, while Cinder is more devious and power - hungry. In fanfiction, this contrast can lead to some intense character - driven stories where they either learn from each other or clash in more complex ways than in the original series.