In RWBY fanfiction, the 'Black Knight' could be a variety of original characters created by different authors. It might be a mysterious figure with a dark backstory, perhaps having some sort of vendetta against the main characters or being involved in a shadowy plot within the RWBY universe as envisioned by the fanfic writer.
Often, the Black Knight in RWBY fanfiction is depicted as having a menacing appearance. They may have a large, imposing figure, with a suit of black armor that is either highly decorated or very plain but still gives off an air of danger.
One interesting RWBY Black Knight fanfiction could be one where the Black Knight has a secret past that is gradually revealed. Maybe he was once a part of an ancient order and his actions in the RWBY world are related to fulfilling an old prophecy.
Well, 'rwby our knight fanfiction' might center around a self - inserted knight into the RWBY world. This knight could interact with the main RWBY characters, perhaps joining their team on missions. They could bring new combat styles and moral codes, and the story could explore how they adapt to the RWBY world and how the RWBY characters react to this new addition.
I'm not sure specifically as there could be many different interpretations of this fanfiction. It might be about a lone knight in the Remnant world of RWBY, perhaps on a quest or facing some great challenges.
Fanfiction.net is also a great place to find RWBY Black Knight fanfictions. There are many different stories with various takes on the character. However, the quality may vary, so you might need to read a few summaries or reviews before diving into a particular one.
Since it's a fanfiction, it could have the main RWBY characters like Ruby, Weiss, Blake, and Yang interacting with the knight character. Maybe the knight is the new central figure, or perhaps it's a story that focuses on how one of the existing RWBY characters takes on the role of a knight in some form.
Well, surely the Knight is a main character. They are the one on the path of redemption. And the RWBY team members - Ruby, Weiss, Blake, and Yang - are likely to be main characters as well. They could be the ones who inspire the Knight's change or the ones who the Knight has to prove themselves to.
One common theme is redemption. The Rusted Knight often has a past that he is trying to make up for. Another is heroism. Despite his rusted state, he still tries to be a hero.