[Natsurin]

I thought about it just now, but I have a question, and a wonder.

Spoiler for Refrain, all of it.:

Spoiler for Just incase someone clicked by accident..:

Was it only Riki's class that went on that particular field trip?
I mean, Haruka isn't in Riki's class, how[if she did] did she end up in the accident?

For my wonder, I'm really curious about what would have happened if Kyousuke hadn't hid himself in the bus..
I mean, if you take it literally, wasn't he the one who wanted the most to strengthen Riki and Rin so that they wouldn't have to face despair?