A possible plotline could be that a new enemy targets Kakashi because of his distinct face features, believing there is some hidden power in his appearance. Naruto then has to protect Kakashi. Another plotline could be a magical spell that gets cast on Kakashi's face, changing his expressions uncontrollably, and Naruto tries to find a way to break the spell.
One possible plotline could be that Kakashi is in a life - threatening situation during a battle against a powerful enemy. Naruto, seeing no other way to save him, uses a powerful and self - sacrificing jutsu that costs him his life. Another plotline might involve Naruto making a deal with some dark force to save Kakashi, but the price is his own life. Or perhaps in a mission gone wrong, Naruto takes a fatal blow meant for Kakashi.
One possible plotline could be that Naruto, being older, has to take on the role of mentoring Kakashi in some new form of ninja art or strategy. Since he has more experience in this fanfiction, he passes on his knowledge.
Well, if there is a 'naruto kills kakashi fanfiction', it would be a very different take on the Naruto universe. It could be set in a world where Naruto has been corrupted by an evil force. This force could be manipulating Naruto's emotions and memories, making him think Kakashi is a threat. In the original series, they have a strong bond, so this would be a very controversial and unexpected plot.
One possible plotline could be that Hanare is in some kind of danger and Naruto and Kakashi team up to protect her. Maybe she has some special knowledge or ability that an enemy wants to get their hands on. Naruto's determination and Kakashi's experience would make for an interesting dynamic as they fight off the bad guys.
One possible plotline could be Naruto growing up with Kakashi's unique training methods. Since Kakashi is known for his strict and strategic training, Naruto might become an even more formidable ninja at a younger age. He could inherit Kakashi's Sharingan abilities in some creative way in this fanfiction world, which would give him a whole new set of skills to master.
One possible plotline could be that Naruto starts to mimic Kakashi's fighting style more closely. Since he looks like Kakashi, people around him might initially mistake him for Kakashi in battle. This could lead to some comical situations, like when his friends are confused about whether it's really Naruto or if Kakashi has some sort of new jutsu that makes him look like Naruto. Another aspect could be that Naruto, in looking like Kakashi, might start to inherit some of the mystery and respect that Kakashi has. Villains might be more cautious around him, thinking he has Kakashi's strategic mind as well.
One possible plotline could be Naruto going back in time and meeting young Kakashi during his ANBU days. Naruto might be shocked to see the cold and distant Kakashi at that time. He could try to break through Kakashi's walls and get to know the real him. Maybe Naruto would share some of his own experiences and wisdom from the future, which could have an impact on Kakashi's development.
Maybe in the fanfiction, Naruto gets injured really badly during a mission. While he is recovering, Kakashi stays by his side constantly, and Naruto realizes the deep care Kakashi has for him, which makes him start to call Kakashi dad. Then, Kakashi helps Naruto train in new ways to get stronger, sharing some of his own hidden techniques and experiences that he hasn't told others before.
One possible plotline could be that Kakashi sacrifices himself in a battle against a powerful new enemy. Maybe he uses his Sharingan to its fullest extent to protect the village, but the strain is too much and he succumbs to his injuries. Another could be that he is poisoned during a mission and despite the efforts of the medical ninja, he passes away, leaving Naruto and the others devastated. This would lead to Naruto being even more determined to achieve peace in Kakashi's memory.
One possible plotline could be that Kakashi realizes his feelings for Sakura during a difficult mission. Maybe they are in a life - or - death situation and he suddenly realizes how much she means to him.