One idea could be Shoko discovers a new, hidden realm in the Land of Ooo. She teams up with Finn and Jake to explore it and uncovers ancient secrets that could change the whole world of Adventure Time.
Lady Rainicorn could also be an interesting character to pair with Shoko. Since Lady Rainicorn can't speak English (in the normal sense), there could be some really fun and comical interactions as Shoko tries to communicate with her. And they could also get into some interesting situations together, like flying around on Lady Rainicorn's back to reach some far - off place.
One great 'Adventure Time Shoko' fanfiction could be about Shoko's adventures in the Land of Ooo before Finn and Jake. It might explore her unique magic and how she interacted with the early inhabitants. Maybe she had a run - in with the Ice King when he was still a bit more menacing and she had to use her wits to escape.
Obviously, Shoko is a main character. She is often depicted as a tough and resourceful girl with her own set of skills. Another important character could be Finn. Finn might cross paths with Shoko and they could either become friends or rivals depending on the plot. Jake, Finn's loyal dog, could also play a role, perhaps helping or hindering Shoko's plans.
Well, a plot could revolve around the return of some old foes in a new form in the future. For instance, the Lich could come back as a more insidious threat that infects the minds of the future inhabitants of Ooo. Also, we could explore the idea of Finn's sword having new powers or a different significance in the future. Maybe it's the key to unlocking a long - forgotten dimension that holds the secrets to saving Ooo from a new impending doom.
One idea could be a new student arriving at Adventure Time Academy who has a mysterious power that no one has seen before. This new character could disrupt the existing social dynamics among Finn, Jake, and their friends.
Maybe Marceline the Vampire Queen teams up with a Dark - type Pokémon in a fanfiction. Since she has a somewhat dark and mysterious personality, it would be interesting to see how she interacts with a Pokémon that shares those traits. For example, she could form a bond with a Umbreon and they could go on adventures together.
One idea could be exploring Finn's family background more deeply. Maybe he discovers a long - lost relative who has a unique power. Another could be about Jake's pups and how they grow up in the Land of Ooo, facing different challenges as a family. Or perhaps a story about Princess Bubblegum's family tree and how it affects her rule in the Candy Kingdom.
One idea could be that the Water Princess discovers a hidden underwater kingdom that has a connection to the Land of Ooo. She has to team up with Finn and Jake to protect it from an evil sea creature.
One idea could be that the OC is a new traveler in the Land of Ooo. They accidentally save the lives of several main characters' love interests. As a result, these characters become attracted to the OC and form a sort of harem around them. For example, Princess Bubblegum's scientific assistant could be among them, drawn to the OC's unique knowledge from another land. Another plot could involve an OC who has a special power that is needed to save the harem members from an ancient curse. This would create a lot of bonding and relationship - building moments.
One idea could be exploring the backstory of the Red Throne. Maybe it was created by an ancient and powerful being for a specific purpose that has been long forgotten in the Adventure Time universe.