Yes, there are many. You can search on popular fanfiction platforms like FanFiction.net or Archive of Our Own. Just use the tags 'Kakashi x Naruto' and exclude the 'lemon' and 'yaoi' tags. There are a lot of great stories that focus on their mentor - mentee relationship or their friendship in a more platonic way.
One major problem is that it goes against the intended nature of the characters. Naruto and Boruto have a father - son relationship in the original series, and this type of fanfic distorts that. Another issue is that 'yaoi lemon' content is often inappropriate and not suitable for a wide audience.
In non - lemon yaoi fanfiction, one interesting aspect is the exploration of their different personalities. Kakashi is the more experienced and reserved one, while Naruto is full of energy and enthusiasm. Their interactions can be really engaging as Naruto tries to break through Kakashi's shell and Kakashi tries to guide Naruto in a more patient way.
One popular theme is their growth as shinobi. It could be about how Naruto learns new jutsus from Kakashi and becomes stronger. Another theme is their bond as comrades. They support each other during tough times in the village.
I'm not aware of any specific 'naruto x boruto yaoi lemon fanfic' as this involves non - canon and often inappropriate themes. However, there are plenty of great Naruto and Boruto fanfics that focus on their relationship in a more positive and canon - friendly way, like those exploring their mentorship or family - like bond.
The characteristics of 'Kakashi x Naruto' hard yaoi fanfiction can be quite complex. It might explore the power dynamics between the two characters in a romantic context. For example, Kakashi being the more experienced ninja could be portrayed as a dominant figure in the relationship, while Naruto's energetic and passionate nature could be used to show his role in the relationship. But again, this is all very different from the Naruto we know in the official story. It's important to note that this type of fanfiction is a form of creative reinterpretation by fans, but it can also be controversial due to its deviation from the original themes.
Personally, I don't recommend seeking out 'hard' yaoi fanfiction as it might contain inappropriate or non - canon content. However, if you're just interested in the relationship between Kakashi and Naruto in a more general sense, there are many normal fanfictions that explore their bond in a positive and interesting way.
One common theme is the exploration of a forbidden love. Since they have a teacher - student relationship in the original series, fanfictions often play with the idea of breaking those boundaries in a romantic context.
To write a good Naruto x Kakashi Yaoi fanfiction, it's important to have a good grasp of the Naruto world setting. Incorporate elements like the ninja techniques, the different clans, and the politics of the village. This will make the story more immersive. Also, build up the relationship gradually. Start with small moments of connection, like Kakashi giving Naruto some extra training or Naruto sharing his food with Kakashi. As for dialogue, make it true to their characters. Naruto might use more simple and enthusiastic language, while Kakashi would be more concise and sometimes sarcastic. Don't forget to add some conflict to the story, whether it's external threats or internal doubts about their relationship.
One common theme is the exploration of their relationship in different scenarios. For example, in some fanfictions, they might be in a secret relationship while dealing with the threats in the ninja world.