Мафия 3. Nightdreams Castle

I didn't quite understand this idea. What's the difference? Did the demonologist kill while "defending" himself from the priest/spy, or was he just going around killing?

It would make sense if, for example, Tengro was a priest or a spy, and he was checking the status of the demonologist, then the killing should have taken place at the demonologist's dwelling... and not at Tengro's apartment...

Also, Tengro was murdered in his own chambers.

So, I think that Am didn't kill Tengro that night, or anyone else for that matter...

Although, of course, I could be wrong.
For reference: I've been following past mafia games... and almost all of my guesses about who is who... were incorrect... :(