What could be the reasons in a fanfic for Sakura to be scared of Sasuke?

Definitely. Fanfic writers often play around with different character dynamics. Sakura being scared of Sasuke can be a part of exploring their relationship in a non - canonical way. It could be due to Sasuke's cold and distant nature, especially after the Uchiha massacre. This fear could be the starting point for many different plotlines in fanfics, such as Sakura trying to understand Sasuke better to get over her fear or Sasuke realizing the impact of his actions on Sakura.

One possible reason could be that Sakura has finally grown tired of Sasuke's aloof and cold behavior towards her. She might have realized that she has been constantly chasing after him while getting little in return, so she decides to ignore him as a form of self - preservation.

Well, one reason could be Sasuke's continued obsession with his revenge. He might be so focused on it that he ignores Sakura's feelings and concerns, which could lead to a fight. For example, if Sakura tries to persuade him to let go of his revenge and he refuses, it could spark an argument.

One possible reason could be that he finally realizes Sakura's unwavering love for him. Throughout their time apart, he might have come to understand how much she truly cared, and now he regrets not being there for her. Also, he could have seen how she grew stronger on her own and feels he missed out on being part of that growth.

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.

There are fanfics like that. Sasuke might leave Sakura for Karin because of Karin's loyalty. Karin has shown unwavering loyalty to Sasuke throughout the series. She was willing to risk her life for him on multiple occasions. In contrast, Sasuke might think that Sakura's love is more of a childhood crush that she hasn't fully grown out of, and he may be drawn to Karin's more mature and selfless loyalty.

One reason could be that Sasuke is very popular and has a lot of fangirls. In the fanfic, Sakura's boyfriend might feel insecure because Sasuke has this charm that attracts everyone. Maybe Sasuke is always achieving great things and getting a lot of attention, which makes the boyfriend jealous as he might feel he can't compete with Sasuke in terms of popularity and achievements.

In the fanfic, it could be that Sasuke doesn't appreciate Sakura enough. She might pour out her love and support for him, but he doesn't return it in the way she hoped. Sakura may have expected a more reciprocal relationship where her feelings are acknowledged and valued. Since that's not the case, she starts to regret her choice of Sasuke.

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.

It could also be due to a misunderstanding. Perhaps there is some misinformation spread about Sasuke in the fanfiction, like false rumors that he has a hidden and malevolent plan. Naruto, being someone who values their friendship deeply, would be scared at the thought of Sasuke turning into an enemy because of these untrue stories.