Thanks for the clarification!
That definition "non-hostile NPCs" is a bit vague. Most of the magisters in Driftwood are "non-hostile". However, if you cast a non-hostile skill of Spirit Vision, they become quite hostile. Who is considered the provoker of the fight in that case?
The adjective "directly" seems a bit vague as well. If some careless person were to chain oil/poison barrels from a place where they knew an opponent would cast AOE to a location near NPCs, who dealt the damage to the NPCs?
One last question. Say the characters that have stolen or "directly" killed a "non-hostile NPC" are characters that were left behind and died on the Lady Vengeance, is the party still flagged as hostile?