Same with casting Living on the Edge during dialog. It's not a secret that when character\npc enters a dialogue it "freezes" for the timeline. So you can buf him and it wont start counting turns until runs off. Living on the Edge doesn't work this way, you see that the buff is on, but won't work when your hp falls to 1, you just die. Only way this skill works properly is to cast it during fight. Dunno if it is a bug or was intended.