Nirvana

Nirvana (涅槃 Nehan) is the true form of the haunted Heavenly Host Elementary School. It is also referred as Heavenly Host Nirvana and the Everafter.

Description
Nirvana is made from red, pulsating flesh with innards scattered on its walls and floors, with eyes and teeth visible in several spots. Some green tentacles will also attack people if they are not careful where they are heading and what they are stepping on.

When Sachiko became its master, it assumed the form of Heavenly Host Elementary School. It consists of a nexus of multiple dimensions inhabited by vengeful spirits. However, after Sachiko was appeased and left the Nirvana, it slowly returned to its original form and went out of control.

Within Nirvana, there are six pillars called the Pillars of the Six Demons which serve as both part of the sealing and its control mechanism. Each one is held by a guardian of some sort, and can apparently only be removed from them safely by a descendant of the Alucard family.

At the core of the Nirvana is Queen, who was the leader of the European witches who were killed during the witch hunts in the middle ages, and also the will of the Nirvana itself.

Anyone who dies within the walls of Nirvana will have their existence erased from the real world and their souls will be trapped inside, forced to relive the pain and suffering of the moment of their deaths over and over for eternity.

There are three known methods to enter the Nirvana:
 * Performing Sachiko in the Everafter charm incorrectly


 * Performing Holy Shroud's Promise charm incorrectly


 * Joining the two halves of the Everafter Stones along with the correct incantation

History
Nirvana was born from the Land of Corpses spell in the Book of Shadows. Yoshie attempted to save her husband, Seiji, who was on the verge of death due to the Alucard curse - all men married into the family will die due to strange illness. Fearing the loss of people she loved and devastated for being unable to save her husband, Yoshie resorted to black magic and casted the Land of Corpses to create a place where she could live together with her husband's soul for eternity and left Sachiko in the real world.

However, the spiritual power that ran through Yoshie's blood was strong enough to create something Yoshie did not intend - the Nirvana, a new dimension where all souls trapped inside will have their existence erased from the real world. However, since the Nirvana also has a mind of its own, Yoshie was unable to control it. Seiji's soul was torn apart and scattered, and Yoshie experienced the blowback as the consequence of casting black magic.

Realizing that her mother was in grave danger, Sachiko swallowed the Nirvana and sealed it within her body thanks to her immense spiritual power. While they were not able to prevent Seiji from dying, his existence was returned after Sachiko sealed the Nirvana. Yoshie, regretting her actions, swore to protect her beloved daughter who housed an entire dimension within her as the consequence of her action.

Wanting to watch over Sachiko closely from where she worked and protect her from danger outside, Yoshie performed a ritual using a paper doll proxy called Spirit in the Everafter. She used Sachiko as the offering (effectively making Sachiko in the Everafter) to make Heavenly Host Elementary School as the site of Sachiko's future death.

On the day of Sachiko's eleventh birthday, Yoshie died after she fell down the stairs when Principal Takamine attempted to rape her. Sachiko, who witnessed the event, was killed by Takamine to seal her mouth about the incident. Since Sachiko was dead, the Nirvana sealed in her body was released into the world once more. Consumed with a grudge over the death of her daughter and herself, Yoshie cursed his family which made Takamine and his son, Yoshikazu, start to lose their sanity over time.

Sachiko, having an immense spiritual power, was reborn as a spirit in the Nirvana, and became the master of the Nirvana which assumed the form of Heavenly Host Elementary School due to it being being the site of Sachiko's death and the effect from the Sachiko in the Everafter ritual.

Fifty years later, Naho, who went to investigate Yoshie's estate, retrieved the paper doll. She then changed the ritual name to the Sachiko Ever After charm and posted the wrong instruction purposefully on her blog to help her mentor's research, leading many people who performed Sachiko Ever After charm to be trapped and die within the walls of Heavenly Host Nirvana.

In a bad ending, Elise Alucard retrieved all the Pillars of the Six Demons in the Nirvana and turned them into Crystals of the Six Demons, which caused the seventh and the last pillar to appear, indicating the coming of the apocalypse as the Nirvana merged with the real world and turned it into the world of death.

After Elise managed to acquire the Book of Shadows and become its properly acknowledged master, she confronted and defeated Queen, then sealed her back into the tome after Elise willingly accepted to share Queen's suffering with her.

Elise then decided to consume the already expanded Nirvana by consuming its flesh walls and sealing it within her body, following what Sachiko previously had done, which allowed all souls trapped within Nirvana to restore their lost existence in the real world. However, since Elise does not possess great spiritual power like Sachiko had, her own existence was taken instead.

Elise later was shown to be in a vegetative state, mumbling her last thoughts when she sealed the Nirvana in her.