First, get to know the characters well. Finn's personality, his values, and his growth throughout Adventure Time are important. Then, think about the concept of the harem. Decide who would be in it and why they are attracted to Finn. For example, you could include Princess Bubblegum because of Finn's heroism.
One common theme is the exploration of relationships. Finn, being the central character, has to navigate through multiple relationships with different characters in the harem. Another theme is character growth. As Finn deals with the harem, he often grows as a person, learning about different personalities and how to interact with them.
One good story could be 'Finn's Multiverse Harem'. It explores Finn traveling through different dimensions and encountering various characters who form an unexpected harem around him. The story is interesting as it shows Finn's growth in dealing with different personalities.
Well, in Adventure Time Finn harem fanfiction, often the different personalities of the characters in Finn's 'harem' are really fun to explore. For example, how Finn would interact with a more serious character compared to a goofy one. It can also show how Finn might grow and change through these different relationships, which adds depth to his character.
There is a fanfiction where Finn accidentally stumbles upon a magical harem. In this story, he has to learn to balance his normal adventuring life with the new dynamics of the harem. It shows his growth as a character as he faces different challenges and emotions related to the harem members. It's quite interesting as it also incorporates elements from the original Adventure Time world, like the use of magic and strange creatures.
Princess Bubblegum could be one. She's smart, powerful, and has a long - standing relationship with Finn. Another could be Flame Princess. Their relationship has always been complex and full of chemistry. And maybe Marceline could also be part of it. She and Finn have a great friendship that could potentially develop into more in the context of a harem fanfic.
One popular Finn Adventure Time harem fanfiction is 'Finn's Multiple Journeys'. It explores Finn having different adventures with multiple characters in a harem - like scenario. Another is 'Finn and His Friends in a New World' which also has elements of a harem concept with Finn interacting in unique ways with various characters from the Adventure Time universe.
In the original Adventure Time, Finn's story is about his journey through Ooo, facing monsters and solving mysteries. However, in Finn harem fanfiction, the story often revolves around his interactions with a group of characters in a more relationship - centered way. For example, in the show, Finn might have a brief encounter with a character, but in the fanfiction, that encounter could develop into a complex relationship dynamic within the 'harem'. Also, the fanfiction may introduce new character traits or backstories for Finn that are not in the original show to better fit the harem concept.
First, you need to understand the characters well. Know Finn's personality - his courage, his naivete at times. Then, think about which characters you want to include in the harem. For example, you could choose characters like Huntress Wizard. Next, create a plot. Maybe Finn discovers a hidden place where all these characters are and they form a unique bond. Keep the Adventure Time feel by using its unique language and the presence of strange lands and creatures.
One possible scenario in this fanfiction could be that Finn's transformation into a vampire brings out a whole new side of his personality. He might struggle with his newfound thirst for blood while still trying to uphold his heroic values. Maybe he teams up with Marceline, who is already a vampire, and she teaches him how to control his urges.
In some Adventure Time fanfictions, Finn might be betrayed by a character he trusted deeply, like Jake. For example, Jake could make a deal that goes against Finn's values in order to protect the Candy Kingdom, leaving Finn feeling betrayed as he sees it as a moral compromise. Another instance could be a new character in the fanfiction who befriends Finn only to steal his magic sword for their own gain.