There are many legends and mysteries in the world, particularly Japan, which is well known for it's own unique ghost stories about demons and gods (the Oni and the Gami/Kami).
What is considered a demon or even a god would be the Inugami (the name means "Dog God" in Japanese). The Inugami is a being that resembles an anthropomorphic dog and is a master in the black arts.
According to traditions, the Inugami can be conjured through a complex and very dark sacrificial ceremony: A common dog must be buried up to its neck and be deprived of any food or water. When the dog is about to perish while being tortured by hallucinations, the head must be severed and then both the head and body must be placed in a well prepared ritual, only then will an Inugami be made.
Families who keep an Inugami within their household are called Inugami-Mochi (meaning "Those who keep a Dog-God as a pet"). However, not all Inugami are loyal and benevolent to their masters, some can turn on their master and even kill them if the master is not a well-trained conjurer. One such Inugami is said to exist, even to this day.
This Inugami is infamous for the haunting of the Kyuki Family Mansion. According to legend, the last member of the Kyuki Family, Sako Kyuki, was a paranoid man, and sought for a way to protect himself and his mansion. His pet Akita Inu, Tobi, was ravaged by an unknown but fatal disease, and in order to gain the protection he desired, Master Kyuki thought it necessary to put his dying dog out of it's misery by sacrificing it. When the ritual succeeded, a strange being was said to have risen from the dark ashes of Tobi's corpse, This creature was obscured by black smoke, wore a dark kimono and had a devilish Akita Inu head and a piercing red gaze, alot different in appearance than any regular Inugami.
For a while, this Inugami protected Master Kyuki and his mansion, but in reality it deceived Master Kyuki for it's own malicious purposes. In secret it killed off Kyuki's friends and servants, and used it's magic to turn them into it's own demonic servants. It drove Kyuki mad, and when the moment came, the Inugami killed Master Kyuki himself, completing it's collection of ghosts. The fiend was after the ownership of the Kyuki Household, hoping to make it a home of nightmares and evil for all those who dare enter it. Ever since then, no one has ever entered the old Kyuki Mansion, and no one was ever heard from again when they did.
In 1978, authorities were investigating the disappearances of 3 teenagers in Kyoto, and it wasn't until they searched the Kyuki Mansion that they began to suspect the hauntings being responsible.
The police found a journal lying around on the 2nd floor of the Mansion, the journal belonging to Hiro Okamodo, one of the three disappeared teenagers.
Here's what the translation of the journal says...
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''"May 21st, 1978,''
''4:23 PM''
''That brilliant Kazuki has done it again, he was able to prepare a trip for him, me and Akiko this weekend, what luck. He said this time it's going to be at the old Kyuki Mansion a few miles out of town.''
''Akiko says she's unsure about going, because she's heard of the old ghost stories that go on at that mansion, how a crazy man that lived there killed his dog to create a guardian, but then the guardian betrayed and killed the madman and now lives in the mansion. Both me and Kazuki assured Akiko that the rumors 'about the mansion are mere old wives tales and that everything was going to be alright.''
''May 24, 1978,''
''12:10 PM''
''Well, here we are, we made it to the Kyuki House, jeez, talk about your fixer-upper, at least it's still liveable at some standard. Kazuki is practically enjoying himself with being here, while Akiko is still nervous about being here. Me, I'm a little unsure of myself, but I cannot shake the feeling that someone's watching us as we enter the mansion, maybe it's just me.''
''2:44 PM''
''We had a nice lunch at the dining room, Akiko's feeling more confident about being in this mansion, I'm glad, maybe it's because we had lunch. As for Kazuki, he's going on about some of the rooms in this house, how particularly interesting and decorative they are. Clearly whoever owned this place has....exotic taste.''
''May 25 1978,''
''8:30 AM''
''Something weird happened last night, I was awoken up suddenly by the sound of something like a knife swiftly slicing through flesh' and then the mad whining of a dog in pain, at least that's what I thought it was, I shrugged it off and went back to sleep.''
''Akiko's back to her unsure self again, she too looks as if she had a hard time sleeping last night, saying a pair of red eyes kept staring at her. Kazuki clearly saw something too, but he doesn't seem to wanna talk about it.''
''Akiko requested that we leave once more, and I almost thought about considering it too if it weren't for Kazuki, who told us that there was no ghost in this house, and said that nothing bad was gonna happen. Maybe he's right, maybe we were just having first night hallucinations.''
''12:30 AM''
''Okay, something's up. I was just woken up by the sound of someone laughing, and then I thought I saw a tall dark figure standing at the foot of my bed looking at me until it vanished like smoke before I could have any chance to get a better look at it. And then I noticed that my room was covered by small inscription papers, all of them having one word...."Death".''
''What the hell is going on?''
''May 26th,''
''6 AM''
''Oh my god, Akiko's gone missing, we didn't find her in her room and we've looked all over the house, and as we were looking we kept seeing bizarre hallucinations that look like the previous owners of the house, not only that, whenever we tried getting out of the house we end up back in the same foyer we came out of! Kazuki's acting very strange, he just told me that this was my fault that this is happening. What the hell? He was the one who told us to come here in the first place, why is he placing the blame on me? He almost attacked me saying many odd things, like Akiko and I were out to get him or I was nothing but trouble...My god...the look on his face, it was maddening. I dunno where he stormed off to now, but now I'm scared, Akiko's missing and Kazuki's probably losing his mind. I just want to go home...''
''8:30 AM''
''Okay, Kazuki seems to have calmed down, saying he's sorry for being the real cause of all this and just blaming me, though I dunno if I can trust him anymore, though now's not the time for that. We need to look for Akiko.''
''5:30 PM''
''.....We just got attacked by a ghost, it looked like a woman that had her neck snapped, Kazuki's practically beside himself now, he ran off screaming that he can't take this anymore. I can't explain more right now, I need to go after him.''
''5:42 PM''
''I managed to calm Kazuki down. My goodness, I've never seen him so broken up, he looks as if he's about ready to kill himself. Not now. We need to find Akiko.''
''8:21 PM''
''More ghosts, these ones...my god....these ones looked as if they were killed in the most cruelest ways, I can't even describe it. Not only that we keep seeing the same doglike creature in some rooms, this was definitely the same one I thought I saw the other night. Is that thing the one causing this? Are the rumors true?''
''9:00 PM''
''No....No please, don't let it be true....Kazuki...he's...he's gone...He tried to kill himself...I tried to tell him not to...but...that thing....it finished the job...it killed Kazuki and ran off with his body...''
''I gotta get outta here.''
''I don't even know if Akiko's alive either, that monster probably had gotten to her too...''
But it won't get me, I'm gonna get out of here whether it wants me to or not!
''2:40''
''It's after me, it knows I'm trying to get out.''
''What is this thing?''
''What does it want?!''