Dark Apocrypha

Dark Apocrypha also known as Twisted Grimoire of Dark Forces is a powerful sacred gear that is almost as old as the True Longinus, originating from biblical times. Despite not being a Longinus, the sacred gear is shown to be immensely powerful, allowing its wielder to fight on par to high level creatures due to what the sacred gear lacks in power, it makes up in with in strong magical abilities. The sacred gear is seen as a curse for angels and other creatures of light such as the Celestial Spirits of Gaia. However a very unique twist of this sacred gear is that the spirit inside can actively possess it's wielder, allowing the witch to gain full control of their body for a limited amount of times. It was because of this that the God of the Bible used to have a angel watch over the wielder which led to the death of a few angels giving the sacred gear the nickname "Light Slayer". The Greek Goddess Nyx has even called the sacred gear a "disgusting thing".

Summary
Somewhere around 6-4 B.C. there existed a powerful psychic girl by the name of Ciara, at 14 she had the special ability to read minds and to siphon the darkness from people's hearts and souls. Using this ability she cured insanity which were believed by the people of her ability to be "exorcisms", she also used this ability to reform murderers, thieves, and a wide variety of criminals, also using her ability to prevent these crimes. Because of these actions she was regarded as a "holy woman". Two years later, after having been bestowed many gifts by the people of her village, there existed a group of girls that were envious of everything she had been given. They then began to make up stories about Ciara being a witch, how she would tempt other girls into sin, and an array of other lies. One day at Sunset, Ciara approached the lying girls to try to get rid of their envy however when Ciara placed her hand on the girl, the girl stabbed Ciara with a knife revealing that she had her own psychic ability, known as camouflague.

When Ciara was stabbed with the knife, this triggered a chain reaction that caused all the darkness that Ciara had spent years siphoning from the villagers to be released, causing fear, paranoia, anger, and hatred to spread over the villagers. It was at this time, the villagers began to regard Ciara as a witch and had the girl chained up and burnt on a stake.

For the first time in Ciara's life she felt an emotion she had never experienced before, hatred. She then released all the psychic powers from her body and thus created a world Ajuka describes as "The edge between chaos and order, between sanity and insanity". This world then became known as the "Edge".

After her supposed death, it is revealed that Ciara managed to survive, with her spirit and the world she created being sealed inside a sacred gear by the God of the Bible to prevent the "Edge" world from destroying the Earth.

Appearance
Dark Apocrypha takes the appearance of an old notebook filled with the story of Ciara, along with numerous spells to describe and imitate the powers she possessed and would've gained if she had lived long enough. There are also pictures of the monsters created by her hatred and anger that reside in "The Edge". Her psychic powers were revealed to be more akin to a magician's spells, and she is regarded as one of the greatest magicians of her time, despite not actually being one. It is revealed by Azazel that numerous fallen angels tried to imitate her abilities in order so that they may return to Heaven but none were able to do such a thing.

To someone who doesn't possess the sacred gear if they attempt to read the words within the Grimoire they will gain a intense migraine that is too unbearable for even a God or Super Devil to endure. It is because of this immense security within the sacred gear that it became viewed as a "pseudo-Longinus".

Trivia

 * The reason I show the FF7 scene to represent the possession is because it reflects perfectly and I believe it was one of the most well done scenes of the movie.
 * The history of this sacred gear was a reflection of Jesus Christ, a holy individual who was betrayed by those they tried to help.
 * This sacred gear is also a mirror of the Salem Witch Trial, with paranoia and darkness leading people do do crazy and irrational things (however with teh Salemn Witch Trial the paranoia and darkness was natural meanwhile for this sacrde gear it was artifically constructed).
 * I had this sacred gear idea for about a year now but only decided to make this sacred gear today after believing my lore for it was decent now.
 * This sacred gear is a rarity among normal sacred gears, with it's creation being to prevent a world-wide catastrophe.