we didn't know when we'll all die, don't be mean to others and if you do, hurry up and make up with them, otherwise you might lost the chance to say sorry
You can see tears in the friends eyes on page 6. Also you can even see her forcing herself not to scream on the same page and especially on page 8, the willpower she had to save her friend..
Hyakumonogatari is usually translated as "100 ghost stories", but I think it just covers horror in general. The word itself doesn't even mention what kind of story, literally it's "100 stories".
Not sure, though. I'm not a word scientist. And you'd think that if the point was to cause a supernatural event to occur, they'd have to be supernatural stories.
Maybe he'll get to the end and nothing will happen because he screwed up on story 8 lol.