Suppose in the fanfiction Sakura constantly undermines Naruto's efforts to become Hokage. She might spread rumors or say negative things about his capabilities in front of others. Given that Naruto's dream of becoming Hokage is his life's motivation and something he has worked so hard for, this would surely make him angry. His anger is justified because she is attacking his most precious goal and self - esteem.
If Sakura betrays Naruto's trust in the fanfiction. For example, she might tell Naruto's secrets to the enemy. Naruto has always been very open and loyal to Sakura, so this would be a huge blow to him. His anger would be completely understandable as she would have broken the bond of trust between them.
In a scenario where Sakura physically attacks Naruto out of the blue without any good reason in the fanfiction. Naruto has always considered Sakura as a friend, and an unprovoked attack would be a shock. His anger would be a natural response to such an unjust act. After all, no one would be happy to be physically assaulted by someone they trust and care about.
Danzo could also be the one to make Naruto angry. Danzo's underhanded tactics and secrets might be exposed in the fanfiction, and if they were to directly harm Naruto's friends or the village, Naruto would be furious at his actions.
It could strain their friendship. Naruto might start avoiding Sakura, which would make her realize she's done something wrong and try to fix it.
Yes, there might be such fanfictions out there in the vast world of fan - created content. However, it's important to note that fanfictions can vary greatly in quality and adherence to the original spirit of the Naruto series.
One possible reason could be if Sakura constantly criticizes Naruto's abilities in a very harsh way. In the story, Naruto has always been striving to prove himself, and if Sakura doesn't show any faith in him, it might make him angry.
His anger could lead to a complete breakdown of their relationship in some fanfictions. Naruto might feel so betrayed or frustrated that he decides he doesn't want to be around Sakura anymore. But in other fanfictions, it could be a turning point for their relationship. Naruto's anger might make Sakura see him in a new light, as someone who has his own boundaries and feelings, and she might start to respect him more, which could improve their relationship.
Naruto may become more guarded. After being cheated on by Sakura, he'll be less likely to open up to people easily. He might seem tougher on the outside.
He could also distance himself from them. Naruto might choose to avoid his family, not wanting to be around them as a way to show his anger. He could move out or stop participating in family activities.
His family might have neglected him in some ways. Naruto grew up alone and feeling unwanted in the original story. If in the fanfiction, his family was around but still didn't give him the love and attention he needed, it would be a valid reason for his anger. He has always craved connection and acceptance, and if his family failed to provide that, he would be furious.
In some fanfictions, it could be a situation involving a curse or a dark magic that Sakura doesn't understand. She has exhausted all her medical and ninja knowledge but to no avail. Naruto, on the other hand, has had experiences with all sorts of strange and powerful forces, so she begs him for help in order to save someone or something she cares about.
In 'naruto gets angry fanfiction', one possible scenario could be that Naruto gets angry when he discovers someone has been mistreating his friends in the village. He might immediately confront the wrongdoer with his signature rasengan at the ready.