Pillars of the Six Demons (六鬼門の柱 Roku Kimon no Hashira , lit. Pillars of the Six Demonic Directions or Pillars of the Six Weaknesses) are pillars that serve as both part of the sealing and control mechanism of the Nirvana. Each one is held by a guardian of some sort, and can apparently only be removed from them safely by a descendant of Shinozaki family. However, removal of the pillars from the guardians turns them into Crystals of the Six Demons (六鬼門結晶 Roku Kimon Kesshō , lit. Crystals of the Six Demonic Directions or Crystals of the Six Weaknesses) and also serves to aggravate the Nirvana making it more likely to waken.
They reside in the North, Northeast, Northwest, Southeast, Southwest, and South direction of Heavenly Host Elementary School.
When all six pillars (also collectively called as "sephira") have been gathered, they turn into a round crystal with black sheen called Kabbalah Dogra (涅槃の結晶 (カバラ＝ドグラ) Nehan no Kesshō (Kabara Dogura) , lit. Crystal of Nirvana (Kabbalah Dogra)).
There are seven pillars / crystals / sephira in total, with the last one appear after other six have been gathered.
- Sephirot of Justice (正義 Seigi) - A pink crystal found in the clearing by the covered walkway in the South.
- Sephirot of Honor (光栄 Kōei) - An amber crystal found in the 2nd floor Art room in the South West.
- Sephirot of Victory (勝利 Shōri) - A green crystal found in the gymnasium in the North West.
- Sephirot of Mercy (慈悲 Jihi) - A navy blue crystal found at the bottom of the pool in the South East.
- Sephirot of Base (基礎 Kiso) - A purple crystal found inside the 1st floor staff room of the annex in the North East.
- Sephirot of Crown (王冠 Ōkan) - A white crystal found at the top of the bell tower in the North.
- Sephirot of Knowledge (知識 Chishiki) - A pillar of light at the bell tower.
- Kimon (鬼門, lit. Demon Gates) traditionally means Northeast direction, and is superstitiously believed to be the direction where demons go in and out, hence it's strongly advised to avoid it. This direction is believed to be unlucky and people who believe in this superstition usually avoid their houses or offices to face northeast. It can also mean weaknesses, as in something a person is not good at (e.g. math, cooking, etc).