One idea could be a male oc who is a new student in Riverdale. He has a mysterious past related to a big city crime syndicate. As he tries to fit in at Riverdale High, he gets involved with the core group of friends. Maybe he has some special skills like being an expert in martial arts or a whiz at hacking, which he uses to help solve the town's mysteries. Another plot could be that he is an aspiring musician who gets caught up in the drama between the music clubs at school and the local music scene in Riverdale. He could also have a romantic sub - plot with one of the female characters, like Betty or Veronica, but there are obstacles in their relationship due to his secrets.
One idea could be creating an OC who is a new student at Riverdale High. This OC could have a mysterious past that slowly unfolds throughout the story, like being related to an old Riverdale family no one knew about. They could get involved in the drama between the Bulldogs and the Southside Serpents, trying to bring peace. Another idea is an OC who is a journalist for the school paper, uncovering secrets that even Jughead hasn't found yet.
Well, perhaps it's a case of mistaken identity. A new character in Riverdale is kidnapped instead of the intended target, who was thought to be Archie because of his popularity. This could lead to a series of events where the other characters have to race against time to find the kidnapped person before it's too late. They might discover new secrets about the town and its inhabitants during the search.
One idea could be that a vampire from TVD ends up in Riverdale. Maybe Damon Salvatore finds himself in the small town for some mysterious reason. He could get involved with the mystery-solving that the Riverdale gang is always up to. He might use his vampire charm and powers to help or sometimes complicate things. Another plot could be that a character from Riverdale discovers the existence of vampires and werewolves like in TVD. For example, Jughead could be intrigued by these supernatural beings and start writing a story about them, which then draws the attention of the TVD characters.
One idea could be that a strange meta - human from The Flash's world somehow ends up in Riverdale. This meta - human has the power to manipulate memories, and starts causing chaos by making the Riverdale characters forget important things about each other. Archie and his friends then team up with Barry Allen to stop this meta - human before their town is torn apart.
A plot idea could be that the villains from Naruto, like Orochimaru, somehow end up in Riverdale and start causing chaos. The Riverdale gang has to team up with Naruto and his friends to stop Orochimaru's evil plans. Another idea is that the Riverdale characters gain some ninja abilities and use them to solve their own town - related problems.
In some 'Riverdale Crossover Fanfiction', a crossover with a time - travel plot is really engaging. For example, when the Riverdale gang travels back in time to the 1950s and has to deal with the different social norms while also trying to get back to their own time. Also, crossovers with other teen drama shows where they have to compete in a singing or dancing competition together can be quite entertaining.
A male oc could be a supernatural being, like a half - vampire or something similar. He comes to Ikebukuro in search of a cure for his condition. Along the way, he befriends some of the main characters, such as Mikado and Kida, and together they uncover secrets about his origin that are linked to the long - forgotten history of the city.
Maybe the Hufflepuff male OC is an exceptional flyer, even though Hufflepuff isn't known for Quidditch. He tries out for the team and faces discrimination from some of the other houses at first. But through his hard work and kind nature, he not only makes the team but also helps to bring unity among the different houses in the Quidditch matches.
Well, a plot could be that the male OC is a time - traveler. He arrives in Camelot during Merlin's time and has knowledge of future events. This causes a stir as Merlin tries to figure out if he can trust this stranger. Maybe the OC is from a future where magic has been fully accepted and he tries to bring that ideology to Camelot. Or perhaps the male OC is an artist who uses magic in his art, and his works start to have strange effects on the people of Camelot, leading Merlin to investigate.
A great plot could be that the male OC is a street magician in Gotham. One day, he discovers that his magic tricks are actually real magic due to an ancient artifact he found. He then uses this magic to fight crime, but he has to keep it a secret from the authorities and the criminal underworld. Or perhaps the male OC is a detective who has a unique ability to see the memories of the dead. This helps him solve crimes that no one else can, but it also takes a toll on his mental health as he is constantly exposed to the trauma of the victims. Another plot could be that he's a young heir to a wealthy family who decides to use his family's resources to fight against the poverty and crime in Gotham instead of living a life of luxury.