One problem is that it goes against the natural family relationship in the Naruto series. Naruto is Boruto's father, and creating a yaoi relationship between them is inappropriate and distorts the family dynamic.
There could also be an ancient evil that was sealed away long ago but is now awakened due to the changes in the ninja world. This evil force could possess people or create chaos in the villages. Boruto and Naruto would have to figure out how to stop it, perhaps by seeking out old allies and learning forgotten jutsu.
Another idea is a 'what - if' scenario. For example, what if Boruto was raised in a world where Naruto had failed to become Hokage? This could lead to a very different Boruto, perhaps more cynical or desperate to change the world on his own. The fanfic could explore how he would grow up and try to fix the situation his father couldn't.
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 Boruto x Naruto fanfic, often the character development can be quite fascinating. For example, we could see how Boruto deals with the legacy of his father, Naruto. Writers might create scenarios where Boruto has to face challenges that test his understanding of his father's ideals and his own path. It also allows for a deeper look into Naruto's role as a father and how he imparts his values to Boruto.
A plot where Naruto and Boruto have to team up to fight a new, powerful enemy that neither could defeat alone. This would allow for some great father - son bonding moments and also show how their skills complement each other. For example, Naruto's brute strength combined with Boruto's unique ninja techniques. It could also explore how Naruto imparts his wisdom about the ninja way to Boruto during the battle.
Obviously Naruto and Boruto themselves are the most essential characters. But Sasuke can also be a great addition. His relationship with Naruto is well - known, and his skills and experience can add depth to the story. He could act as a mentor to Boruto as well.
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.
First, understand the characters well. Know Naruto's and Boruto's personalities, their goals, and what makes them who they are. Then, think of a unique situation or plot that can bring them together in a romantic way, like a special mission only they can go on.
One popular Boruto x Naruto yaoi time travel fanfic is 'A New Chance'. It takes Naruto back in time and explores his relationship with Boruto in a different timeline. The story has great character development and an interesting plot that keeps you hooked.