For the 'Murder House' season, an OC could be a real - estate agent who unknowingly gets involved with the haunted house. They start experiencing strange things and gradually discover the dark secrets of the house. Their character arc could be about how they deal with this newfound horror and whether they try to expose the truth or run away from it.
One idea could be creating an OC (Original Character) who is a new patient at the asylum in 'American Horror Story: Asylum'. This OC could have a unique backstory, like being a psychic who was wrongly committed. They could interact with the existing characters, such as Sister Jude, and their psychic abilities could either help or hinder them in the asylum's crazy environment.
A cool 'ahs coven crossover fanfiction' idea could be a crossover with a fairytale world. The coven witches could find themselves in a land of fairytales. They might meet characters like Snow White or Cinderella. The witches' powers would be very different from the magic in the fairytale world, and this contrast could lead to some exciting adventures. Maybe they have to help a fairytale character break a curse using their unique witchcraft.
One idea could be to cross Kit with a character from another AHS season. For example, Kit meeting the witches from Coven. He could bring his own brand of mystery and charm to the witchy world. Maybe he gets caught up in their power struggles.
A possible fanfiction could involve Edward Mordrake in a different time period. For example, what if he was transported to the modern day? How would he interact with the new world? There could also be a story where he forms an unlikely alliance with another AHS character to fight a common evil.
First, know the 'American Horror Story' universe well. Watch all the seasons you want to base your OC in. Then, create your OC. Decide on their appearance, personality, and backstory. For example, if it's for 'Hotel' season, your OC could be a vampire hunter with a tragic past that led them to hunt vampires. Next, think about the plot. How will your OC interact with the existing characters and the setting? You can start with a simple idea like your OC checking into the hotel for a specific reason and then things start to go wrong.
Perhaps an OC is a young archaeology student who idolizes Nathan Drake. They manage to get involved in one of his expeditions through sheer determination. Along the way, they learn from Drake and also teach him new things about modern archaeological research methods. It could be a story of growth and adventure for both characters.
Well, you could have an OC that is a skilled hacker who gets involved with the Phantom Thieves by accident. They might have a Persona that represents a famous code - breaker from history. Also, an OC who is a foreign exchange student from a country with a very different cultural background could bring in new elements to the fanfiction. Their Persona could be influenced by their home country's folklore. Maybe an OC who is a prodigy artist and uses their art skills to create powerful items in the Metaverse, with a Persona related to a great artist from the past.
You could have an OC that is a young witch who idolizes Bayonetta. She tries to copy Bayonetta's style and fighting techniques but often fails in a comical way at first. As the story progresses, she discovers her own unique way of being a witch. Or an OC who is a cursed object collector. This OC comes across Bayonetta when investigating a powerful cursed object and they end up working together to either destroy or control the object's power.
One idea could be an OC who is a spy sent to infiltrate Doflamingo's organization. This OC could have a hidden past that slowly gets revealed as they gain Doflamingo's trust. Another idea is an OC with a special power that Doflamingo wants to control or use for his own evil plans. For example, the OC might be able to manipulate time in a small area, which could be a great asset in battles or heists.
One idea could be to create an OC who is a new dancer in town. This OC could bring a different style of dancing to Footloose's world, like a fusion of modern and traditional dance. They could face challenges in getting the town to accept this new form of expression.
A great concept for superhero oc fanfiction is a hero who has the power of empathy. They can sense the emotions of others and use that to either calm down villains or boost the morale of their fellow superheroes. Also, you could write about a superhero oc from another dimension who comes to our world with powers that are completely alien to our understanding, like the ability to turn into a living energy form.