One possible plotline could be that Sakura, perhaps under the influence of some dark force or a misunderstanding, physically attacks Naruto. This could be due to a false belief that Naruto has done something terrible to their village or friends. Another plotline might involve Sakura's words hurting Naruto deeply. For example, if she tells him that he will never be good enough or that she doesn't really consider him a true friend after all. It could also be that Sakura's actions in pursuit of Sasuke end up causing Naruto pain indirectly, like if she constantly ignores Naruto's feelings for her while she chases Sasuke, making Naruto feel unimportant and hurt.
In fanfiction, Sakura might hurt Naruto in a more emotional way. Maybe she accidentally reveals a secret that Naruto has been keeping, which makes him the target of others' scorn or danger. For instance, if Naruto has a hidden power or past that he doesn't want known, and Sakura blurts it out. Or, she could be influenced by Orochimaru or some other villain to turn against Naruto. This would not only cause physical harm but also a great deal of emotional turmoil for Naruto as he would be betrayed by someone he considered a close friend.
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.
A plotline could be that Hana is jealous of Naruto's popularity or power. So, she decides to challenge him and in the heat of the battle, she ends up hurting him. Naruto, on the other hand, is shocked by her actions and tries to talk to her to find out why she did it. This could then turn into a story about friendship and forgiveness, as Naruto may choose to forgive Hana and help her overcome her jealousy issues.
In the fanfic, it might be set in an alternate universe where Sakura has a different personality. She could be more aggressive and competitive with Naruto. During a sparring match, she goes too far and seriously hurts Naruto. This could then be the starting point of a story about Naruto having to forgive her and them rebuilding their friendship.
One possible plotline could be Naruto being forced to serve Orochimaru due to some sort of blackmail or threat against his friends in Konoha. Maybe Orochimaru has some information that could endanger Naruto's loved ones if he doesn't comply. Another aspect could be Naruto initially pretending to serve while actually trying to find a way to take Orochimaru down from the inside. This would add an element of mystery and deception to the story.
Well, in some fanfics, Sakura might be jealous of Naruto's growing power and relationship with others. So she could try to undermine him, which in turn hurts Naruto. Maybe she spreads false rumors about him in the village. Another idea is that Sakura is forced to choose between Naruto and Sasuke in a dangerous situation, and her choice, even if it's not completely her fault, ends up hurting Naruto deeply. It could also be that Sakura's overzealous medical treatment, in an attempt to save Naruto from a serious injury, actually causes him more pain and harm.
One possible plotline could be that Sakura realizes her feelings for both Naruto and Sasuke are more than just friendship. She might become possessive out of fear of losing them. For example, she could try to keep them from going on dangerous missions alone. Another could be in a post - war scenario where she sees other people getting close to Naruto and Sasuke and her possessiveness kicks in as she has been through so much with them. She might start small, like being extra clingy, and then it could develop into more complex relationship dynamics as the story progresses.
Well, in some fanfictions, it could be that Lucy is under a curse. This curse makes her act out of character and she ends up hurting Natsu. Maybe she is cursed to attack the closest person to her, and at that moment, it's Natsu. Or it could be a situation where Lucy is forced to choose between saving herself and Natsu in a dangerous situation, and her choice, even if it's to save herself, could be seen as hurting Natsu. Also, there could be a plot where Lucy is brainwashed by an enemy who wants to break the bond between her and Natsu, and as a result, she causes him harm.
Well, perhaps Itachi is under the influence of a genjutsu himself when he captures Sakura. He could be acting against his own will. Sakura, in this situation, might try to break the genjutsu on Itachi while also trying to free herself. And during this time, she could discover some secrets about Itachi's past or his true motives that were hidden before. This could lead to a complex relationship between them where Sakura has a new perspective on Itachi, not just as an enemy but as a victim too.
One possible plotline could be that Sakura, being emotionless, is on a solo mission. She approaches every obstacle with cold efficiency, not showing fear or hesitation. Her lack of emotion might make her more calculating in battle, relying solely on her skills and strategic thinking.
One possible plotline could be that Sakura realizes Hinata has a closer relationship with Naruto than she does. So, she starts to feel jealous. For example, she might notice how Naruto always seems to have a soft spot for Hinata's gentle nature. This could lead to Sakura trying to prove herself better in Naruto's eyes, like training extra hard or taking on more difficult missions.