I just read a story, well, a sequel to Love Live! and it's called "My heart will always be here"
Unfortunately, it's in Vietnamese so most of you can't read it.

I don't want to translate it because I was terrified after finishing the story. 
It's all about killing characters (YES, ALL 9 OF THEM ARE DEAD) by a mysterious yet familiar person. That story has a sequel as well, but that is just the same as the main story! Tragic ending for all of the characters! I EVEN READ THAT THERE'S A FAKE NICO YAZAWA GO WITH MUSE AND MAKI COMMITTED SUICIDE BY FALLING OFF A CLIFF!!!

(That suicide is in the sequel)

I have read killing stories (like the second year trio manga) but that is the most terrifying story I have ever read.

I actually think that I will have nightmares from this.

PLEASE. HELP. ME.