If Naruto died and Sasuke became Hokage, it would be a very different Konoha. Sasuke, with his brooding and somewhat isolated nature, might rule with a more strict hand. He would likely focus on security and protecting the village from external threats. His past experiences with the dark side might make him extra vigilant. However, he would also have to deal with the loss of Naruto, his long - time rival and friend, which could add a layer of melancholy to his rule.
One possibility is that Naruto might feel a sense of isolation. Since Sasuke has achieved the highest position in the village, Naruto might feel like his own journey and achievements are overshadowed. He could become cold as he withdraws into himself, thinking that he no longer has a clear purpose in the village where his best friend now holds all the power.
The village would be in shock at first. Naruto was a beloved figure, so his death would be a great loss. But they would also have to accept Sasuke as Hokage. Some might be hesitant as Sasuke has a dark past. However, his actions in protecting the village in the past, like during the Fourth Shinobi War, would give him some credibility. The older generation who knew Sasuke from his early days might be more accepting, while the younger ones might be a bit scared of his cold exterior.
Well, usually it starts with Sasuke realizing his newfound leadership role. He might struggle at first with the political side of being Hokage, which is very different from his combat skills. Naruto would be there to support him, of course. And then they would face some new threats to the village together. The story could also explore how Sasuke changes the way the village is run, maybe bringing in some new ninja training methods inspired by his own experiences.
The dynamic would shift a bit. Naruto would have to balance his friendship with Sasuke and his duties as Hokage. He would probably try to bring Sasuke more into the fold of the village, making him feel like a true part of it. Sasuke, in turn, would start to see the village in a new light, through Naruto's leadership. Their relationship would be a key factor in the stability and growth of the village.
Their relationship could become more of a partnership. With Naruto as Hokage, Sasuke might be more willing to work within the village's framework. They would still have their friendly rivalry, but it would be more focused on making the village better.
Naruto could become cold due to disappointment. He might have expected Sasuke to rule in a certain way, but when Sasuke becomes Hokage and starts making decisions that seem contrary to Naruto's ideals, Naruto feels let down. This disappointment could turn him cold towards Sasuke and the village in general.
They still have that deep friendship, but it's more official. Naruto as Hokage respects Sasuke's views on matters related to the outside threats. Sasuke, on the other hand, respects Naruto's leadership. They often meet to discuss strategies and how to keep Konoha and the ninja world in peace. For example, they might plan together how to deal with any potential threats from rogue ninjas or other villages.
In a fanfic scenario, Naruto as Hokage might have some concerns about Sasuke being in the Anbu. He could worry that Sasuke's past and his more solitary nature might not fit well with the Anbu's group dynamics. However, Sasuke proves himself by using his unique skills and insights to protect the village. Meanwhile, Naruto tries to integrate Sasuke more into the village's core, leading to some interesting character - development moments for both of them.
A really interesting fanfiction idea could be that Sasuke in the Anbu discovers a conspiracy within the village that even Naruto as Hokage is unaware of. Sasuke then has to decide whether to go to Naruto directly or investigate further on his own. This would create a lot of tension and drama, as Sasuke's loyalty to the village and his relationship with Naruto are both at stake.