The Wise Man's Sabbath

The Wise Man's Sabbath is a key event and major plot point in the story High School DxD Spirits of the Damned. It was an event held by the Old Satan Faction, in an attempt to gather enough power to overthrow the current Four Satans.

Plot History
The Wise Man's Sabbath is an event that is held every 500 years, specifically on the Winter Solstice. The one who holds the Sabbath is the magician known as the Wise Man, a powerful sorcerer who is said to have lived far longer than the average human. Rumors say that he discovered the secrets of immortality, but whether or not this is true is unconfirmed. The Sabbath is held for various reasons; sometimes it is held for the purpose of harvesting energy, other times it is used as a celebration for the turning point of the century. However, some have used the Sabbath for personal gain as well, and the Wise Man does nothing to stop them, due to that he is a neutral party. His role is merely to begin the Sabbath, not intervene in it's process.

In 2000, the Sabbath was held, and hosted by the Old Satan Faction. The purpose behind the Sabbath's function was to drain the humans of their life energy, and then use it to obtain enough power to obliterate the current Satans. To this end, they gathered 500 humans with exceedingly strong life energy. However, the Sabbath was hijacked by Kazuma Koga, who wished to use the Sabbath to become a being more powerful than God. As a result, 498 human lives were lost, leaving only two survivors; a pair of siblings who were taken from their home. Kazuma had succeeded in becoming a more powerful being; he had become a Devil on equal footing with Sirzechs Lucifer.

However, the Sabbath had another effect. One of the survivors, Ikari Maigo, had unknowingly absorbed the demonic energy that was released as excess from Kazuma's ascension, and turned him into a Hellion, a human who possessed demonic power, which would turn him into a Devil should the power consume him. As with previous Sabbaths, the Wise Man did nothing to interfere with the ceremony, but he declared the ritual now forbidden, and would not hold it again unless circumstances demanded it of him.

Outcome
With Kazuma now a demon on par with Sirzechs Lucifer, the Old Satan Faction attempted to recruit him, with the purpose of obtaining a powerful ally. Kazuma agreed to do this, but only if he would be the one to obtain the position of Lucifer and rule as the Devil King. Rizevim saw no problem with that, and agreed. Kazuma then noticed the only living survivors. He was surprised to see that someone had managed to survive, and pondered what to do with them. Rizevim then gave the suggestion that he should take the girl as his bride, in order to establish a lineage, albeit in a joking manner. Kazuma, delighted by this idea, took his suggestion to heart. To Ikari's horror, he watched as Kazuma proceeded to rape his sister, Kira, in front of him, but because of his weakened state as a result of the demonic energy flowing into him, he was unable to do anything.

After falling unconscious, Ikari awoke in the Wise Man's home, who informed him of what happened. Ikari was livid with what had transpired, and demanded why the man did nothing to stop the Sabbath, though the magician told him that it was out of his hands, stating that he had made a pact to not interfere with the ritual since he first created it. However, after the events, he swore to Ikari that he would not hold it again, unless circumstances demanded it of him. Worried about his sister, and her mental state, Ikari asked if Kira was okay. The Wise Man said that she was in a coma, likely due to the traumatic shock, and that she was now harboring a demonic seed in her body. Kazuma was unable to impregnate her with normal means, so instead, he implanted a portion of his own essence into her; a parasite that would feed off of her. According to the Wise Man, once the seed has matured, it will hatch and emerge from her body, killing her in the process.

Ikari, horrified, asks how much time she has left. The Wise Man informs him that the seed will hatch once Kira has turned seventeen; the legal age of marriage, and that the only way to destroy the seed without killing her would be to kill the one who put it inside of her. In order to save his sister, Ikari must kill Kazuma in three years, otherwise his sister will die. Seeking strength, Ikari asks the Wise Man to train him, and the old man complies, though he warns that he may die as a result.

Survivors

 * Kazuma Koga (Ascended to Devil Status)
 * Ikari Maigo (Became Hellion)
 * Kira Maigo (Comatose State)

Trivia

 * The Wise Man's Sabbath is mainly inspired by the Eclipse Event in the Berserk series.