There's a legend that runs through the hills of Japan about a macabre box crafted with the bones of many sinful people, and it's called "Satsuriku No Tenshi", or carnage and death. Some around that region believe it to be made from the very mind of a twisted man that believe building the remains of his spiritual family around this accursed box would keep whatever is in it out. He found it in a haunted village in these hills, curiously bringing back to his house, where strange things started to happen to him and his wife. He started to have these strange dreams of a dark figure trying to kill him. Then he started to hallucinate things, horrible things that eventually took his sanity and made him yearn to get rid of the box, but no matter how many times he tried to get rid of the Satsuriku No Tenshi, it came back with a stronger vegeance. His wife began to worry about him as he slowly feel deep into insanity. He eventually killed his wife, beat her death on suspicion of being a demon out to kill him, and he took his own life to rid himself of the vile box. Now it sits in these hills outside of Japan, lying in this unfortunate man's house to be found by another person.
(Before anyone takes offense to my japanese, I would to make one thing clear: I looked it up. If I got it wrong, please tell me and don't be a jerk about it. )