During the Lady Boyle demonstration you give a letter to a guy and are immediately challenged to a duel. Now one way you can get around it is to freeze time after he fires, possess him and walk him in front of his own bullet. Does this count as you killing someone? I want to make my first run through kill free, but also want to get as many side missions as possible. Just skipping this part is not a real solution because there might be many missions that result in a similar situation. I guess I just want clear guidelines on what counts as a "kill".

Hmm a tough situation really, since you're the reason why he dies, and yet you didn't strike the blow.
I think it's best left up to a fellow from Arkane to give the right answer, I am however puzzled by this question too!

However in that situation, why not bend time, and shoot him with a sleep dart?(IF they are of course unlocked in that mission at all)
Then it's a no-kill for sure

I would say so, yes. Cause the other option is to walk away..which is more non lethal

I would say so, yes. Cause the other option is to walk away..which is more non lethal

Agreed.

I would think it counts as a kill simply because your intent was to have the guard killed, by his own bullet, via your ability to possess him.

Optionally, you could possess him and leave him in the girl's bathroom and then make your escape.

good question. will the game count it as a kill if you indirectly cause someone else's death????

Another question might be, would this kill count towards the chaos system?

I think the kill would could since you had your hand in him dieing.