Obviously Naruto himself. There might also be some new characters that he meets in this other world. And depending on how the story goes, there could be versions of his friends from his own world, like Sasuke or Sakura, even if they are different in some way in this new world.
Well, it could be about Naruto finding himself in a strange new world where he has lost his friends and is mourning their absence. Maybe he's trying to find a way back to his own world while dealing with his grief.
Physically, Naruto can use his Rasengan or other powerful jutsus to fend off enemies attacking Boruto. His combat skills are top - notch, and he won't hesitate to engage in battle to keep Boruto safe.
In the 'boruto kills naruto fanfiction', a motive could be a power struggle. Boruto might believe that Naruto's power is holding back the village's growth or his own potential. He could think that by eliminating Naruto, he can bring about a new era of power in the Hidden Leaf. Also, it could be out of desperation. If Boruto is in a situation where he believes that killing Naruto is the only way to save someone he loves, like his mother or a friend, he might take such a drastic step.
Maybe it's the high expectations that Naruto has for Boruto. Naruto is a hero, and he might unknowingly put a lot of pressure on Boruto to follow in his footsteps. Boruto could be scared of not being able to meet those expectations.
They could start by having an honest conversation. Naruto could sit down with Boruto and just listen to his fears without judgment. This would be a first step in building a better relationship.
An example of a wife mourning her husband is as follows:
1 "Qing Ping Diao (1)"
Although the mountain oath is written in brocade, it is difficult to entrust it.
Don't let youth ruin youth.
the road to Jiuquan turns dusty and my clothes are full of dust.
I dream of returning to Nanpu, my sleeves full of tears.
2. The Phoenix with a Head: The Feelings of the World
The world's feelings are thin, human feelings are evil, the rain sends the evening flowers easy to fall.
The morning breeze drips away tears, I want to write a letter, my heart is sad, I speak alone.
3 Song of Everlasting Regret
In the green garden, the morning dew waits for the sun to dry.
In spring, all things in the world shine.
I often worry that the yellow flowers will wither when the autumn festival comes.
When will the rivers flow east to the sea and return to the west?
When young and strong, you don't work hard. When old, you feel sad.
These poems were all about how a wife mourned for her husband, expressing the deep feelings and irreparable rupture between husband and wife.
Sasuke is very likely to be involved. He has a close relationship with Naruto and is also an important figure in Boruto's life. His skills and knowledge could be crucial in any adventure or situation that Naruto and Boruto find themselves in. Another character could be Hinata. As Naruto's wife, she would surely be concerned about any strange events involving Naruto. And for Boruto, she is his mother, so she would play a role in any family - related or village - threatening situations.