Kawaki makes his appearance in Boruto manga at a specific point, but I can't recall exactly. You might want to check the official manga sources for the precise chapter.
It could also be related to a prophecy or a pre - determined fate in the fanfic's plot. There might be some kind of dark prophecy that says Kawaki has to kill Naruto to prevent a greater evil. Or perhaps Kawaki is being controlled by an external force that has a vendetta against Naruto and uses Kawaki as a tool to carry out the murder.
The main people behind the Boruto manga are Ukyo Kodachi and Mikio Ikemoto. Their collaboration has resulted in an engaging and popular manga that expands on the Naruto universe.
In Boruto manga, some significant characters have met their demise. The deaths often play a crucial role in driving the plot and adding drama. However, specific names depend on the latest chapters and story arcs.
One common theme is friendship. Writers often explore how Himawari and Kawaki, who come from different backgrounds, form a bond of friendship. Another theme is growth. They both grow as characters, learning from each other.
It could be a rogue ninja who has a personal vendetta against Boruto's family. This ninja might have caused harm to Boruto's father Naruto in the past, and now Boruto is determined to make him pay.