Every NPC can be killed, but doing so lowers your SEN (sanity). Low SEN causes the music to vanish, dialogue to become incomprehensible, and horrifying hidden entities to appear.
If you are searching for that "rar" file, you are essentially looking for the keys to a labyrinth. Whether you find it on or through community-driven translation projects like Withered Gryphon , remember that Black Souls 2 blacksouls2rar full