No. Fanfiction is a form of creative expression. Naruto fans write fanfiction to explore different ideas and stories within the Naruto world. Just because someone doesn't like it doesn't mean it should be 'killed'.
One idea could be that Naruto and Sasuke are somehow transported to the world of Kill la Kill. They might get involved in the fight against the Life Fibers, with their ninja skills being a unique addition. Maybe Naruto's Rasengan could be used to disrupt the Life Fibers in a new way.
One aspect of this fanfiction could be the exploration of the harsh realities within the Naruto universe. It might show characters being forced to make difficult choices between killing their opponents or being killed themselves. This could lead to a deeper understanding of the moral gray areas that exist in a world full of ninja battles and power struggles.
One interesting crossover is when the ninjutsu from Naruto is combined with the combat style of Kill la Kill. For instance, Naruto using his shadow clone jutsu while Ryuko uses her scissor blade attacks in tandem. It creates a very dynamic and visually appealing fight sequence.
Maybe Kakashi could be the one. He's always been Naruto's mentor in many ways. He has the knowledge and skills to train Naruto for such an unusual task. He could use his Sharingan to analyze the fanfiction and teach Naruto how to spot the dangerous elements within it.
Perhaps Naruto discovers a forbidden music jutsu. This jutsu allows him to turn music into a physical force. When he sings or plays an instrument, the music creates sharp blades of sound that can cut through his enemies. He might also be able to use the rhythm of the music to disrupt the enemy's chakra flow, causing them to collapse and die.
A reason could be that Itachi is framed as a traitor to the Leaf Village in the fanfiction. Naruto, being the defender of the Leaf, would then see Itachi as an enemy and take action to kill him to uphold the village's safety and honor.
Sure. One popular 'naruto and kill la kill fanfiction' might be the ones that explore the characters from both universes teaming up for a special mission. For example, Naruto and Ryuko could join forces to fight a common enemy that somehow threatens both their worlds. It could be an interesting concept as Naruto's ninja skills and Ryuko's kamui powers would make for an exciting combination.
He might kill an enemy shinobi from another village. For instance, if there is a particularly aggressive and cruel shinobi from the Sand Village during the Chunin Exams who poses a great threat to Naruto's friends or the Leaf Village in general, Naruto could be forced to kill him in self - defense or to protect others.