Aragami
40 Achievements
EA Play
Pacifist
Obtain all 'Kami' medals
How to unlock the Pacifist achievement in Aragami - Definitive Guide
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.