I'm working on Ghost Hunt #10, and since this is the first half of the arc I thought I should research a bit about the rest of the arc before I continue translating. Because there's so many questionable parts in the story that can be taken many ways. (And translated many ways).
So I read a person's spoiler review (in Japanese) online.
It helped a lot.
So now that I know the ending and the secrets Naru's been hiding, I notice a lot of foreshadowing in the previous volumes.
Hm. Now it all makes sense. Like Naru's office name, why he travels a lot, why he wears black, etc...
It's really too bad that the novels are out of print. They look pretty interesting.