Oh, I remember playing Iji! I think that was the first game I played that noticed and reacted if you tried to play as a pacifist. There was at least one unavoidable boss fight when I played it though, as I recall.

Digging back through my old disks, it looks like I actually still have my copy from 2008 (version 1.2, according to the manual.txt file) as well as a saved game from much later when I replayed it in February 2013. That was a while ago!