In a future Naruto and Kakashi fanfiction, Naruto could gain the ability to communicate with all living things. This would help him in understanding the needs of the village and the surrounding nature. Kakashi, on the other hand, might develop a new Sharingan ability that allows him to see the future in a very limited way, like seeing the next move of his opponent a few seconds in advance. This would enhance his combat skills significantly.
In this fanfiction, it could also be about Naruto going back in time to learn from Kakashi. Since Kakashi was a great ninja in the past, Naruto might want to gain some skills or wisdom that he didn't have the chance to learn before. They could form a unique bond during this time, different from their relationship in Naruto's original timeline. Kakashi could be initially suspicious of this strange Naruto from the future but gradually come to trust and mentor him.
In future Naruto and Kakashi fanfiction, their relationship could be one of mentorship still. Naruto, now a powerful Hokage, might seek Kakashi's wisdom on handling complex political situations in the village. Kakashi, with his years of experience, could offer valuable insights. They could also have a more equal friendship, sharing stories of their past adventures over a cup of tea.
One possible plot twist could be that Naruto's love for Kakashi from the past disrupts the timeline. Maybe his feelings cause him to unknowingly change events that were supposed to happen. For example, he might prevent Kakashi from making a certain decision that was crucial in the original timeline.
It could develop in a really interesting way. Since Naruto is from the future, he might have knowledge that he uses to protect Kakashi. This would make Kakashi curious about Naruto. As they interact more, they could start to develop a deep bond. Naruto might share some of his future experiences with Kakashi in a veiled way, and Kakashi would start to see Naruto in a different light, leading to a relationship that is based on mutual respect and a bit of mystery.
Well, there could be. Fanfiction writers love to explore unique and unexpected relationships. Since Naruto and Kakashi are both popular characters in the Naruto universe, some writers might come up with such a plot for the sake of creativity and exploring different storylines. But it's not a part of the official Naruto story.
Sasuke could be a popular character. He might be involved in the story in a way that either helps or hinders the situation where Naruto hurts Kakashi. For example, if Sasuke tries to stop Naruto from doing something stupid that would hurt Kakashi.
Another reason could be related to Kakashi's past actions. If there are some secrets or things Kakashi did in the past that come to light and Naruto doesn't like them, he could snap at Kakashi. Naruto has a strong sense of justice and loyalty, so if he feels betrayed or misled by Kakashi, his reaction could be to snap.
Kakashi might be initially surprised. But then, he would probably use it as a teaching moment for Naruto. He could say something like 'Naruto, stealing is not the way of a ninja.' And then give him a punishment like extra training.
The theme of friendship is also prevalent. Despite the time difference, they form a strong bond. They might start off as strangers, but as they work together towards a common goal, their friendship deepens. In some fanfictions, this friendship could even change the entire Naruto universe's future. Additionally, the theme of self - discovery is often explored. Naruto may learn more about his own roots and past through his interactions with Kakashi, and Kakashi may discover new aspects of himself with Naruto's influence.