One idea could be an alien oc who has the ability to blend into human society but is on a secret mission to protect Earth from a greater alien threat. Another could be an alien oc with a unique form of communication that causes chaos when humans try to understand it. Maybe an alien oc that is stranded on Earth and has to adapt to human customs in order to survive and find a way back home.
Well, you could have an 'aliens oc fanfic' where the alien oc is a shapeshifter. It could take on different forms to explore different aspects of human nature. For example, it might become a child to experience human innocence, or an elderly person to understand mortality. Or perhaps an alien oc that comes from a planet where art is a form of currency and tries to introduce this concept to Earth, leading to all kinds of cultural clashes and revelations.
One idea could be that the aliens are actually friendly but are misunderstood at first. They came to Earth to learn about human emotions and end up helping the family in the attic deal with their own internal problems.
One idea could be a story where the monsters and aliens have to team up against an even greater threat from another dimension. Maybe a powerful interdimensional being that wants to conquer both Earth and the alien planets.
A hobbit OC fanfic could focus on a young hobbit who dreams of leaving the Shire to become a great warrior. They set out on a journey against the wishes of their family and face many challenges. Along the way, they meet different races like elves and dwarves and learn from them, all while trying to prove themselves in a world that doesn't expect much from hobbits in terms of combat.
One idea could be creating an OC that is a hybrid of different Pokemon types. For example, a Pokemon with the features of a water - type and an electric - type. This could lead to unique abilities and an interesting backstory about how it came to be. Another idea is to have an OC that is a trainer from a far - off, unexplored region. This trainer could have different training methods and a whole new set of Pokemon not commonly seen in the main Pokemon world. You could also make an OC that is a Pokemon with a special power related to emotions, like it can heal other Pokemon's wounds when they are sad or boost their power when they are happy.
An OC in a Grojband fanfic could be a time - traveler from the future. They come back to the present day where Grojband exists and tries to change the course of the band's history. Maybe they know that the band is going to face a big obstacle in the future and they want to prevent it. This OC could introduce futuristic music technology to Grojband, making their music even more extraordinary.
Well, in 'oc reincarnation fanfic', one interesting idea could be the transformation of the original character (oc). Maybe the oc is reincarnated into a completely different world with new abilities and challenges. For example, an oc who was a simple villager in their previous life might be reincarnated as a powerful mage in a magical realm. Another idea could be the exploration of past memories in the new life. The oc could have flashes of their former self and use that knowledge to their advantage in the new world.
One idea could be creating an OC who is a master of disguise. They could use this skill to gather information and try to outwit the mastermind. Another idea is an OC with a unique phobia that adds an interesting twist to the killing game scenario. For example, an OC who is terrified of the dark and has to face challenges in a pitch - black area.
One idea could be to create an OC (Original Character) who is a new rider in Horseland and has a special bond with a wild horse that no one else can tame. This OC could bring new adventures and challenges to the Horseland community.
You could have an OC who is a shy artist fairy. In the fanfic, Tinkerbell discovers the OC's amazing talent for painting the most beautiful landscapes of Neverland. They then team up to create a huge mural in Pixie Hollow that showcases all the different areas of their magical world. The OC might start off really timid but gain confidence with Tinkerbell's encouragement.
You could make an OC that is a lost heir to a great Magi kingdom. This OC has been raised in obscurity but discovers their true heritage. Their journey could involve learning about the politics, magic, and culture of the Magi kingdom they are heir to. They might face opposition from those who don't want them to claim the throne. You could also focus on an OC who is a nomadic mage, traveling from one place to another in the Magi world, collecting different types of magic and having various encounters with other mages, djinns, and characters from the original Magi story.