One of the most popular characters is Ulfric Stormcloak. His role in the Skyrim civil war is a great starting point for fanfiction. Some stories might explore his motives more deeply, or what could have happened if he had won the war without the Dragonborn's interference. Another popular character is Vivec. His god - like status and his complex history in Morrowind make him a fascinating subject for fanfiction. Writers can explore his relationship with other gods or how his actions in the past still affect Tamriel in the present. Also, Cicero from the Dark Brotherhood is often a fan favorite. His insanity and loyalty to the Brotherhood are great elements for creating engaging fanfiction stories.
Well, first off, Martin Septim is quite popular. Even though his story ended in Oblivion, fanfiction writers often bring him back. They might explore what he could have done if he had survived. The Dark Brotherhood characters, especially the Listener, are also popular. Stories about their assassinations and the inner workings of the Brotherhood are always interesting. And Nocturnal, the Daedric Prince of Night and Thieves. Her mysterious nature and her influence on the Thieves Guild in Skyrim make her a character that many fanfiction authors like to write about. They might create stories where the protagonist has to deal with her demands or her curses.
The Dragonborn is extremely popular. Since they are the main protagonist in Skyrim, they are often the center of many fanfiction stories. People like to explore their backstories further, like where they came from before the events of the game. Another popular character is Sheogorath. His chaotic and unpredictable nature makes for great storytelling. Writers can put him in all sorts of strange situations. And then there's Serana. Her vampire nature and her complex relationship with the Dragonborn in the Dawnguard DLC make her a favorite among fans, who often write about her post - Dawnguard adventures or her past.