One popular theme is his relationship with other characters in the series. For example, his interactions with Dazai can lead to some really interesting fanfic scenarios. Another theme could be exploring his backstory more in - depth, like his time in the Port Mafia before the main events of the story. Also, his powers and how he might develop them further in different situations are often explored in fanfics.
Well, it's hard to name the 'best' as it's subjective. But some authors who are well - known in the community are often those who have a deep understanding of chuuya's character. They are able to capture his essence, his fiery personality, and his complex relationships. You can usually find these authors by looking at the ones with high ratings and lots of positive reviews on fanfic platforms.
Friendship and rivalry are also common themes. He might form unexpected friendships with characters from the crossover world, or he could develop rivalries. In a crossover with a detective - themed world, he could be both a friend and a rival to the local detectives, with their different methods of solving problems creating interesting interactions.
There's also 'Chuuya Nakahara Meets the Avengers'. In this fanfiction, Chuuya gets transported to the Marvel Universe. His no - nonsense attitude and powerful combat abilities make him an interesting addition to the Avengers team. He has some intense battles with the villains while also trying to figure out how to get back to his own world.
Chuuya is not dead in the manga. The author has kept him alive to drive the story forward and create interesting developments. His presence adds a lot of excitement and intrigue to the plot.
Most BSD light novels often have complex characters. Since they are based on literary figures, they bring in the depth and complexity of those original personas. For example, a character might have the same traits as a famous writer but with a unique twist for the BSD universe.