I really like how the author chooses to write this story. Like, the first chapter was slow with just a bit of a shock (Mitsu's death) but then bam, a finger that was mysteriously cut!
Then, using the mystery of the finger, the author hooked us readers in, and we're drawn into the lives of the characters. Each new chapter give the characters more depth and make us relate/feel more about them. The mystery is still there, but it's no longer the focus of the story.
Of course, the story could be told in chronological order, but it wouldn't make as much impact as this.