I watched the Kyoukai no Kanata anime. So I was wondering if the anime adapted the light novel closely.
As far as I know the story is different from around episode 3 onwards, because the light novels were still being written while the anime was being produced
I've only read the fan translation of the first one and a half volume and as far as I know the entire hollow shadow thing wasn't even in the light novels.
Also, the Mirai-hen movie with the amnesia was anime original.