There were a few novels that could be recommended to readers who liked to regret the supporting characters after the main character died. Among them," They Regret After the Female Lead's Death " and " His Opponent Regrets After Breaking the Marriage " were novels that described the regret of the supporting characters after the main character died. These novels could satisfy the readers 'preferences for this plot.
In the novel, the protagonist Fan Xian did not die in any of the chapters. Thus, Fan Xian, the protagonist of the celebration, did not die in the novel.
You might consider 'Steins;Gate'. The plot takes unexpected turns, and in some cases, the main character's fate is quite tragic. It's a sci-fi visual novel with a lot of depth and twists.
I'd recommend 'Echoes of the Void.' The main character's death in this novel is a powerful and unexpected conclusion that leaves a lasting impact. It's not a typical ending but gives the story a unique depth.
In 'Game of Thrones,' several main characters meet their demise before the end. For instance, Ned Stark's death early on sets the tone for the series' unpredictable and often brutal nature.
Miyuki could be the main character. She is known for her intelligence. In the fanfic, she could use her intelligence to try and find a way to bring Konata back, perhaps through some science - fiction - like means. This could lead to her exploring some uncharted territories of knowledge and having to make some difficult decisions about whether it's right to interfere with death in such a way.