One event could be if Hinata is forced by her family to make a decision that goes against Naruto's wishes. For example, if her family arranges a marriage for her with someone else, Naruto might be angry at her for not standing up to them. He values freedom and choice, and if he thinks Hinata is giving in too easily, it could make him angry.
In a fanfiction world, if there is a power struggle in the village and Hinata takes a side that Naruto opposes. Naruto has his own ideas about how the village should be run and protected. If Hinata aligns herself with a group that Naruto believes is harmful to Konoha, he could be angry at her for what he sees as a wrong choice.
If Hinata were to accidentally harm someone Naruto cares deeply about, like one of his friends from Team 7. Naruto has strong bonds with his friends, and any harm to them, even if accidental, might cause him to lash out at Hinata in anger. He might not immediately understand the situation or be too quick to judge in the heat of the moment.
One possible reason could be misrepresentation of her character. In some fanfictions, authors might change her personality to fit a certain plot, like making her overly jealous or mean, which would be out of character for the gentle Hinata. This could make her seem unlikable and thus anger fans who love the original Hinata.
Another reason could be in a fan - created scenario where there are secrets involved. Hinata might be keeping a secret from Naruto that, when revealed, makes Naruto feel betrayed or deceived. This sense of betrayal could easily turn into anger. For instance, if Hinata has a connection to an enemy that she's been hiding from Naruto.
Perhaps Hinata decides to be more assertive and tells Naruto how she really feels about him. Her honesty and vulnerability could be the trigger that makes Naruto finally see her as more than just a friend or acquaintance. He might start to look at her in a different light and really notice all the things that make her special.
One possible event is that Hinata witnesses Naruto's amazing skills in a sparring match during academy training. She's impressed by his tenacity and decides to approach him, starting their friendship.
Maybe the villagers were being ungrateful for his past sacrifices. Minato was the one who saved the village from the Nine - Tails' attack. If they started to forget his deeds or were misusing the peace he had brought, he would be angry. He might have thought that his efforts were in vain if the villagers didn't uphold the values he fought for.
Maybe Sakura makes a decision that endangers herself or the team without consulting Naruto. In the world of Naruto, they are a team, and Naruto values his comrades. If Sakura does something reckless like that, it could make him angry.
Well, the plot might involve Naruto's arrogance leading to a rift between him and his friends. Hinata, being the observant and kind - hearted person she is, decides to confront Naruto. She could start by showing him how his new - found arrogance is affecting those around him, like how it's making the younger ninjas in the village feel discouraged. Then, through a series of events, like going on a mission together where Naruto's arrogance almost gets them in trouble, he starts to see the error of his ways.
In the fanfiction, Sakura could be jealous because she has an ego. She might have thought that Naruto would always be there waiting for her. But when he falls for Hinata, it bruises her ego. Additionally, she may have seen Naruto as her safety net, someone who would always support her no matter what. Losing that special status to Hinata makes her envious and jealous.
It can create division. Some fans might defend the fanfiction, saying it's a creative interpretation, while those who are angry about Hinata's portrayal might oppose it strongly. This can lead to arguments and a split in the community.
In fanfiction, Harry Potter might be angry if his friends are in danger and no one seems to be taking it seriously. He's very protective of his friends, like Ron and Hermione. So if some authority figures in the story are being dismissive of the threats his friends face, that would surely make him angry.