In a fanfic where Sasuke accidentally kills Sakura, the story would take a tragic turn. Firstly, Sasuke's character arc would be derailed. He has always been on a path of seeking power and revenge, but this would add a whole new layer of self - loathing and despair. Sakura's death would also impact the medical ninja system in the Leaf Village as she was a talented medic. Her friends like Ino would be devastated. Moreover, it could lead to a series of events where Sasuke tries to make amends in his own way, perhaps by taking on dangerous missions alone to atone for his mistake, which would be a huge departure from the original story.
Well, in such a fanfic, it would completely shatter the original dynamics. Sasuke killing Sakura accidentally means that all the hopes of their relationship, whether it was friendship or the potential for more, are gone. The Leaf Village would be in mourning. Sasuke might become a hunted man, not just for his previous actions but now for this unforgivable act. And the Akatsuki, if they get wind of it, could try to use it to their advantage, either by recruiting a guilt - ridden Sasuke or by causing more chaos in the already shaken village.
There might be some extremely niche and dark fanfics that involve such a plot, but it's not something that is mainstream or widely promoted. Most fanfics in the Naruto fandom tend to focus on more positive relationships, character development, or alternative storylines that don't involve such tragic and self - harm - related concepts. If it does exist, it would likely be in some less - known or more edgy fanfic communities.
In this fanfic, Sasuke's character would change in terms of his cold exterior. He would soften up a great deal. He might start smiling more often, especially when he is around Sakura. His actions would also be more focused on pleasing her rather than just his own goals. For instance, he might accompany Sakura to the hospital where she works just to be with her, which is a big change from his usually self - centered nature.
He could also become more vengeful. If Sakura's death was caused by an enemy, Sasuke would stop at nothing to avenge her. His focus would shift solely to seeking revenge, and his already formidable skills would be honed even further in his quest for retribution.
Perhaps Sasuke was testing Sakura's loyalty or strength. He may have thought that if she couldn't withstand his aggression, she wasn't worthy of being in his life. Also, his own inner demons, like the hatred he carried from his past, could have flared up and led him to almost kill her without fully realizing what he was doing.
One possible reason could be that Sakura has grown and changed a great deal. Maybe she has become stronger both physically and mentally, and this newfound strength and confidence are what draw Sasuke to her. For example, if she has made significant contributions to the village or has mastered some new and powerful jutsu, Sasuke would start to see her in a new light.
Perhaps in the fanfic, Sasuke was being pushed to his limits. He was so intent on protecting the village from a powerful threat that he didn't realize Sakura was in a dangerous position. His Sharingan might have malfunctioned in some way, causing him to misinterpret Sakura's movements as hostile. Or, there could be a situation where an enemy was using Sakura as a shield, and Sasuke's attempt to strike the enemy ended up harming Sakura instead, all in a split - second decision.
The relationship would become very tense. Naruto would likely avoid Sakura and Sasuke. There would be no more of the friendly banter or the complex emotional triangle that was there before. It's a complete shift from their normal relationships in the original story.
Some fanfic authors portray Sasuke's dreams about Sakura as a form of self - reflection. He sees different versions of her in his dreams, representing different aspects of their relationship. It could be that in one dream, he sees the Sakura from their childhood, symbolizing innocence and the start of their connection. In another, he might see her as a strong and capable ninja, showing how he's come to respect her over time.
In the fanfic, it might be because of a misunderstanding. For example, Sasuke could be wrongly accused of something, and Sakura, believing the false rumors, is so disappointed in him that she refuses to talk. Or perhaps Sasuke accidentally said something really offensive during an argument, which made Sakura so angry that she just cut off communication.
One possible fanfic could be where Sasuke and Sakura's relationship has developed to a point where they are expecting a child. It could focus on Sakura's journey through the pregnancy, her emotions, and how Sasuke is dealing with the upcoming addition to their family. Maybe it shows Sasuke becoming more protective and Sakura being excited yet a bit nervous about motherhood.