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.
I'm not entirely sure specifically what 'osu day to story' is. It could potentially be a personal or local concept within a certain community related to the osu! game, perhaps a creative project where daily experiences in the osu! world are turned into a story.
Sure, the OSU Library has fiction books. It is a comprehensive library that caters to the diverse interests of its users. The fiction collection includes books from all over the world. These books not only provide entertainment but also offer insights into different cultures and ways of thinking. Moreover, the library constantly updates its collection to include the latest and most popular fiction works, so there's always something new to discover.
I think it might be a love story with a dark and gritty edge. Maybe the characters face life-threatening situations or have to make tough choices that put their love to the test, all within the context of the osu world.
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.
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.