An interesting OC for a fanfiction could be a reformed villain. Maybe they were once one of the worst villains but had a change of heart. They could then use their knowledge of the villain underworld to help WordGirl. Another concept is an OC with telepathic abilities. They can sense when villains are about to strike and warn WordGirl. And an OC who creates inventions that either assist WordGirl or are accidentally used by villains.
You could have an OC that is an alien who lands in the city and initially causes chaos because they don't understand Earth's ways. WordGirl has to teach the alien about right and wrong while also dealing with other villains. Also, an OC that is a student at Becky's school who discovers WordGirl's secret identity and has to decide whether to keep it or expose it. And a magical OC who uses spells to either help or hinder WordGirl's missions.
One idea could be to explore WordGirl's origin story more in - depth. Maybe show how she discovered her powers and the initial challenges she faced in using them for good. Another idea is to create a story where WordGirl teams up with a new superhero or sidekick, and they have to overcome a unique villain.
One idea could be that on WordGirl's birthday, all the villains in the city decide to throw her a surprise party. They realize how much she actually does to keep the city in order and want to show their appreciation in a fun way. Maybe they all bake really bad-tasting cakes because they don't quite understand human cooking, but WordGirl is still really touched.
One idea could be creating an OC who has a unique power related to time manipulation. They could be from a different dimension and end up in the Avengers' world. Another idea is an OC who is a master of ancient magic and teams up with Doctor Strange within the Avengers group. Maybe an OC that is a super - intelligent android created by a villain but has a change of heart and joins the Avengers.
You could create an OC for your Persona OC fanfiction who is an artist. This artist OC could use their art as a way to understand and even manipulate the Metaverse. For example, they might draw scenes from the Metaverse that give clues about upcoming events or hidden locations. Their art could also be a form of therapy for other characters who are struggling with their dual lives in the real world and the Metaverse.
Perhaps an OC who is a half - human, half - beast creature. This OC could struggle with acceptance in both the human and beast - kin societies. They end up meeting the main characters during their adventures and learn to embrace their unique identity with the help of the group, while also adding their own combat skills, which are a blend of human strategy and beast - like strength, to the team.
One idea could be to explore the Riddler's origin story from the perspective of your original character (OC). Maybe your OC is a detective trying to solve the mystery of the Riddler's first crime spree. Another idea is to have your OC be a sidekick of the Riddler, either willingly or by being forced into it. They could then have a complex relationship where the OC tries to influence the Riddler's actions for better or worse.
One idea could be an OC who is a brilliant scientist in the Fallout world. They could be working on a secret project to reverse the effects of radiation. Another idea is an OC who is a wandering trader, having all kinds of adventures while traveling from one settlement to another, facing raiders and mutants along the way. And a third idea could be an OC that is part of a new faction trying to bring peace and order to the wasteland.
You could also create an OC human who discovers a hidden talent for communicating with trolls through music. In the fanfiction, this character could use their musical ability to bridge the gap between the two worlds, maybe even creating a new form of harmony between trolls and humans that was previously unthinkable.
One idea could be to create a story where your Bratz OC is a new student in Stilesville. She has a unique fashion sense that both confuses and intrigues the other Bratz girls at first. As the story progresses, they become friends and she helps them design a whole new line of clothing for an upcoming fashion show.
One idea could be creating an OC who is a transfer student with a unique past related to the Dark Hour. For example, they might have had a family member affected by Shadows long before coming to the school. Another idea is an OC with a special ability that doesn't quite fit the normal Persona - using skills that are more about mental manipulation rather than direct combat. And you could also have an OC who is initially a skeptic about the whole Persona thing but slowly gets drawn into it.