[Heian Era]
Year 921: Abe no Seimei. The most famous Onmyouji is born.
Year 993: A band of Oni was said to cause a rampage around the capital. Many young women disappeared, Abe no Seimei performed a divination and determined that the Oni were responsible. Thus the emperor Ichijou orders Minamoto no Raikou, along 'his' four retainers and Fujiwara no Honsho, to exterminate the Oni. Shuten Douji along with 'his' band of Oni were defeated.
Year 1005: Abe no Seimei dies. Leaving two children, One succeed 'his' father as the head of the Onmyouji, while 'his' daughter was sent to marry the into the imperial family.
Year 1119: Emperor Toba has a misterious illness. Abe no Yasuchika performs a divination, exposing the emperor's favorite courtesan, Tamamo no Mae, as an evil Fox Spirit who was eating away the soul of the emperor.
Year 1180: The Genpei War, which the Genji and Heike clans clashed for the control of the nation. The Genji were victorious. Minamoto no Yoshitsune was slain by his own brother Yoritomo to ensure his rule. The Heian Era is over, thus starting the Kamakura Era.
[Kamakura Era]
Year 1274: The Yuan Dynasty invades Yamato. All seemed lost until a very powerful Yokai saved the nation from the Mongol army, the people began to call him "Inu no Taisho", feared and respected by all the people of Yamato.
October of the year 1291: During the tenth month. Two brothers, Abe no Haruyuki and Abe no Tenma, had a vision of a fearsome evil god was going to be resurrected, so they traveled to Izumo to stop the evil from rising.
The two brothers arrived at the temple in Izumo. The elder told them that even if they were powerful magicians, they were still humans and humans can never hope to defeat a god. The only way to defeat the evil god was with the power of the imperial regalia, the Ame no Murakumo or more known as the Kusanagi no Tsurugi.
The brothers felt hopeless, the regalia was lost during the war between the Minamoto and the Taira, thus they had no hope for victory. The only option was to try finding the sword, with the help from the daughters of the elder of the shrine, they found the mythical sword. Both magicians and the priestesses battled against the evil god and thanks to the regalia, they defeated the evil god sending him to the underworld again.
Both brothers married the Priestesses of the Godless Month. The older, Haruyuki, married Chikane and the younger, Tenma, married the Himeko. When they returned to the capital they returned the Kusanagi no Tsurugi. For returning the original regalia to the imperial house, Emperor Fushimi granted them the family name of 'Tsuchimikado', given raise to the Tsuchimikado family. Those events were writen down by a monk under the title of "The Priestesses of the Godless Month".
[Muromachi Era]
January 13 of the year 1336: An strange phenomenon took place in the rural parts of the nation. Tsuchimikado no Kouha and his loyal assistant only known as Rindo, were sent by the shogun to investigate. When they returned, they reported to be an havoc caused by evil yokais but they were able to subjugate them. Curiously enough. Tsuchimikado no Kouha aside from his assistant, he also returned with a girl at his side. He only claimed that her family were eaten by the evil yokai and so he decided to marry her to shelter her in his family. The girl was only known as San, but upon marrying into the Tsuchimikado, she was renamed as, Tsuchimikado no Satsuki.
[Warring States Period to the Edo Era]
January 10 of the year 1446: The Shikon Jewel, the most precious treasure for all the magicians in the nation was shattered and the priestess Kykyo was slain by an half-yokai. Upon that day, series of strange events happen.
