It could be that Anko is under some sort of mind - control in the fanfiction. And because of that, she attacks Naruto without really meaning to. Maybe she has been influenced by an enemy's genjutsu. So, she uses her powerful attacks on Naruto, and he gets hurt as a result.
Naruto might be hurt by fanfiction in various ways. For example, some fanfictions could distort his character. They might portray him as overly cruel or weak, which goes against his original essence in the official story. This can mislead fans who are new to the Naruto universe and create a wrong perception of him.
Maybe she's jealous of Naruto's popularity or his strength. It's possible that she feels overshadowed by him all the time and that jealousy turns into resentment, leading her to hurt Naruto.
It could be due to Sakura's feelings for Sasuke. If she's overly focused on Sasuke and Naruto gets in the way of her plans regarding Sasuke in some way, she might lash out and hurt Naruto without really meaning to cause serious harm.
There are various scenarios that could play out in such a fanfiction. Maybe Naruto was injured during a mission and Kiba stumbles upon him in the forest. Kiba would then likely try to help Naruto, either by getting medical help or using his own skills if he has some knowledge of healing. This could lead to a deeper bond between them as Kiba shows his concern and Naruto is grateful for the assistance.
One possible reason could be a misunderstanding. Maybe Naruto was misidentified as a threat in a tense situation. For example, if there was some sort of dark jutsu at play that clouded Kurenai's judgment and made Naruto seem like an enemy. Another reason might be that Kurenai was under some sort of mind - control. There are many villains in the Naruto universe who are capable of such things. If she was being controlled, she might unknowingly attack Naruto.
There could be a fanfiction where Team Seven is brainwashed or under some sort of mind control. As a result, they turn on Naruto and attack him. This would be extremely hurtful to Naruto, both physically and mentally. He would be confused as to why his friends are suddenly trying to harm him and it would shatter his trust in them.
One popular 'Naruto Hurt' fanfiction could be those that focus on Naruto getting physically injured during a difficult battle and his friends' reactions. For example, some fanfictions might depict him getting hurt in a fight against a powerful new enemy, and Sasuke having to put aside their differences to help him. It often explores the emotional depth of their relationships.
Well, in certain fanfictions, Boruto may physically harm Naruto in a moment of being influenced by dark forces or in a fit of rage. This is often used to create high - drama situations. Maybe he's tricked into believing Naruto is a threat to something he holds dear, like his friends or the village, and so he takes action against him without realizing the truth.
In some fanfictions, Team 7 might hurt Naruto through their words. For example, Sasuke could say something really mean about Naruto's lack of skills compared to his own in the beginning. Sakura might also be dismissive of Naruto's feelings for her in a hurtful way, which could make Naruto feel isolated within the team.