It makes Naruto more complex. Instead of just being the energetic and determined ninja we know, he has a darker side. His tortured past can add depth to his character, making him more relatable as he battles with things like self - doubt and fear.
His relationships with other characters also change. He may be more guarded initially, taking longer to open up to new people. For instance, if a new character enters the story, Naruto might be hesitant to trust them because of what he has been through. His experience of torture in the past can also make him more empathetic towards others who have suffered, which in turn can affect how he interacts with them.
The tortured past can also influence Naruto's goals. Maybe he was originally just focused on becoming Hokage to gain recognition. But after the trauma of being tortured, his goals might shift to also include protecting others from similar fates. He could be more driven to change the ninja world so that no one else has to endure what he did.
Another theme could be revenge. Naruto might be seeking revenge on those who caused his tortured past in the fanfic. This could lead to complex moral dilemmas as he tries to balance his quest for justice with his own values. He may have to decide how far he is willing to go to get retribution.
Naruto might resist through his strong willpower. He has always been determined, and this would not change even under torture. He could keep thinking about his friends in the Leaf Village and his goal of becoming Hokage, which gives him the strength to endure.
Naruto could develop into a more vengeful character at first. The continuous torture by the villagers might make him angry and want to get back at them. But as the story progresses, he might realize that revenge is not the answer and instead focus on making the village a better place for everyone, including himself.
One common trope could be the rescue mission. After Naruto is kidnapped and tortured, his friends or allies would likely embark on a dangerous rescue mission. Another might be the transformation of Naruto's character. The torture could potentially lead to him becoming more jaded or having a new perspective on life. Also, there could be the trope of the villain's motives. The kidnapper might have some convoluted reason for targeting Naruto, like trying to gain power through his unique abilities or to send a message to the Hidden Leaf Village.
In a fanfic, Naruto could be captured by a hidden organization that opposes the Hidden Leaf Village. They might torture him to find out the village's secrets. For example, they could be interested in the location of the Hokage's secret vault or the techniques taught only in the Leaf. Naruto, being strong - willed, would resist as much as he can, but the continuous torture would gradually wear him down.
In such a fanfiction scenario, it can have a huge impact on the plot. Future Naruto has more experience and knowledge. He can train past Naruto in advanced techniques, like better control of the Nine - Tails' chakra. This could potentially change the course of battles in the past. For example, in the fight against Pain, past Naruto might be able to use new skills taught by his future self to win more easily. It also might change Naruto's relationships. If he becomes stronger faster, his friends might view him differently, and enemies might be more cautious.
A plot like Naruto being kidnapped and tortured in a fanfic can really divide the fandom. On one hand, it might attract those who are interested in exploring the psychological and emotional depths that such a situation could bring out in the character. But on the other hand, many traditional fans who are used to the more heroic and upbeat Naruto stories might find it too much to handle. It also might make new fans who stumble upon it have a warped view of what the Naruto franchise is really about.
One possible plot could be Naruto finding a way to overcome the hatred of the villagers through his own strength and determination. Maybe he starts to show his true power and gradually makes the villagers realize their wrongdoings.
One way Naruto could survive is by using his Jinchuriki powers. Even in a tortured state, he might be able to draw on the power of the Nine - Tails to heal himself or resist some of the more severe forms of torture. Also, his training with Jiraiya and others has made him physically and mentally tough. He could use the skills he learned, like the Rasengan, in a defensive way if the torturers get too close. His memories of his friends and the promises he made to them would act as a psychological shield against the continuous pain.