Abe no Seimei

Abe no Seimei (安倍晴明) is the most powerful exorcist mentioned in the series, and additionally, the Miko's enchanted guardian is said to be Abe no Seimei. However, Sayo's enchanted guardian recognizes Rokuro as Abe no Seimei's son, and Hijirimaru said that Abe no Seimei is still alive in Magano, and is currently being a cage that seals away the King of Impurities.

Appearance
1000 years ago, Abe no Seimei was shown as a petite, young woman in a small monk outfit. She appears to have bright-colored hair, white complexion, long eyelashes and sharp eyes. She largely resembles Benio Adashino when she lets her hair down.

Personality
Seimei is a soft, doting person who cares about her child. She has appeared several in Rokuro’s mind to aid him when things get tougher and more dangerous and watch over him.

When meeting Rokuro again after a year, she’s seen as a bubbly, energetic woman, praising her son for his attractiveness. However, she feels extremely guilty about failing to kill the Impurity King, creating Magano and binding countless people to an endless battle.

History
Abe No Seimei was an exorcist and most powerful of all. 1000 years ago, when Impurities roamed freely, Abe No Seimei fought against the King of Impurities. In order to contain it, she created Magano. Before entering, she entrusted her name and ideals to her subordinate, knowing full well that she won't return. She, along with her twelve guardians entered Magano and cornered The King to Tsuchimikado Island. Unexpectedly, the King abandoned his real body and sought to possess her as a final attempt. Unable to remove him from her own body, she turned herself into a flesh cage and has contained the King for over 1000 years since then. At some point in time, she gave birth to Rokuro.

She met Doman Ashiya at some point in 1000 years ago, rescuing him from being slain by a horde of Kegares. Seimei formed a close bond with the man, showing interest in him when Doman’s only passion in life is researching spells, and saying that she wanted to master the way of Yang, while Doman would master the way of Yin, suggesting a close relationship of them. They would look at the shooting stars together and converse about spells, as Doman mentioned himself.

Plot
She appears multiple times in Rokuro's dreams and subtly hints that she is his mother.

When Rokuro is trapped by Sakanashi’s spell, Seimei appears again alongside Doman Ashiya to tell him the true nature of the Impurity King and to help him one last time.

In chapter 79.5, she appears to be bound with the Impurity King, and Doman Ashiya watches her trapped body as he waits till the moment he gets to converse with her arrives.

Powers and Abilities
Abe no Seimei was considered the most powerful exorcist in history. She was capable of creating twelve powerful shikigami which are currently quipped and utillzed by the Twelve Guardians. Moreover, Seimei could even use thousands of hidden techniques and summon among ten thousands of shikigami. She was so powerful that she could seal the Impurity King, a creature said to be extremely powerful, into her own body. Later, she split a part of her power to one of her young apprentice, Doujimaru, letting him use her name and lead the exorcists of yang schools.

Trivia

 * Abe no Seimei is based on the historical onmyōji of the same name.
 * According to Tenma Unomiya, before Abe no Seimei and her twelve allies left to finish off the King of Impurities in Magano, she entrusted a portion of her powers to a young male disciple named Doujimaru and told him to take up her name and guide all excorcists until her return. This disciple would be the Abe no Seimei that the world became familiar with.