Perhaps in the fanfic, Naruto loses his arm in a self - sacrifice move to save his friends. This could lead to a story where his friends feel guilty and Naruto has to convince them that it was his choice. Meanwhile, he tries to adapt to life with one arm and regain his confidence as a shinobi.
One possible plot could be Naruto losing his arm during a battle with a powerful new enemy. He then has to struggle with not only the physical loss but also the emotional and mental toll it takes on him as a ninja. He might have to learn new fighting techniques that don't rely on two arms.
In the context of the fanfic, it could also impact his relationships. His friends might be overly protective, which Naruto may not like. Or, he could inspire others with his determination to keep going despite his injury. It might also change how he is perceived in the ninja world. Some may see him as weakened, while others could view him as even more of a hero for his ability to persevere.
Well, in some 'naruto loses arm fanfiction', it might be a result of a forbidden jutsu gone wrong. Naruto might be exploring a new and dangerous form of power, and the price is his arm. This would then set off a chain of events where he has to find a way to either get his arm back or adapt. He could also face discrimination from some in the ninja community who see him as weakened, but he'd prove them wrong by his unwavering spirit.
Maybe he was protecting someone in Wave. He's always the self - sacrificing type, so he could have put himself in harm's way to save a villager or a friend.
One plotline could be Bucky's struggle to regain his combat skills with a new prosthetic arm. He might face challenges in getting used to its functionality and power. Another could be his search for the people responsible for his arm loss, leading to a revenge - driven storyline. Or perhaps he has to deal with the psychological impact, like nightmares or flashbacks, which could be a major part of the plot as he tries to overcome them.
Well, in this kind of fanfiction, it might be that Sakura loses Naruto because of a misunderstanding. Maybe some false rumors spread about her, and Naruto distances himself from her. Then Sakura has to find a way to clear her name and win back Naruto's trust. Or perhaps Naruto is influenced by some dark force that makes him turn away from Sakura, and she has to fight against this force to get him back.
The main antagonist could be an old enemy who has resurfaced and is more powerful than ever. This enemy targets Naruto specifically and manages to injure him so severely that he loses his arm. For example, Orochimaru could return with new and more deadly powers.
Perhaps in the fanfic, Naruto loses his arm due to a curse or a forbidden jutsu gone wrong. His friends, like Sasuke, then try to find a way to either get him a new arm or help him come to terms with the loss. It could also show Naruto's journey to adapt to his new disability and still be a great ninja, inspiring the younger generation in the process.
One possible storyline could be Percy's journey of learning to adapt to life with one arm. He might struggle at first with simple tasks like getting dressed or holding a weapon. Another could be him facing his enemies who now see him as weakened due to the loss of his arm, but he proves them wrong with his newfound determination and creative combat techniques.
One possible consequence could be a significant change in his fighting style. He might have to rely more on his left side and develop new jutsu techniques that can be executed with one arm. For example, he could focus on enhancing his Rasengan further to compensate for the loss of his right arm's abilities.
Another scenario might be that Naruto sacrifices his arm to save someone he cares about deeply. He might have used his arm to block a fatal attack aimed at a friend or a loved one, showing his selfless nature even in a fan - created story.