Aragami

A 'Kami' medal is earned by completing the chapter without any kills ('boss' enemies excluded, for relevant chapters).

To earn the There's always a choice trophy, you'll need to complete any one chapter without any kills; for the Pacifist trophy, you'll need to do so for all chapters.

Trophy Germany has kindly posted videos demonstrating a no kills playthough of each chapter in a separate thread, found over here.