|Abe no Seimei|
|Romaji||Abe no Seimei|
|Phase||Kuon Phase/Chapter of Kuon|
|“||Doman... What are you thinking...||”|
Abe no Seimei is a powerful onmyoji. Doman considers her as his rival and has a desire to use her to complete the "Kuon" spell. When the news about the strange incidents in the Manor reaches her, she went to investigate it and assumed that the happenings are all the doings of Doman.
Seimei is mentally sharp, cool headed, and have a strong sense of justice. She is very rational, and is not the type who jump to conclusions.
When she reaches the Manor: Tree, she senses that there is something strange about the Mulberry Tree. She finds some spikes in order to seal it, but the spikes are not enough so she has to search again. Sakuya, bloody and exhausted, appears and tells Seimei that she and the other disciples including Kureha and Utsuki are used by Doman to complete his evil plans. She begs Seimei to save Utsuki who is still inside the Underground.
When Seimei sees Utsuki, she is almost attacked by Saiga , but the young girl stop it. Seimei says that it is a good card. Utsuki tells her that it was given by a friend and it is her last card. She tells Seimei that she burned all the hanging corpses to avoid the craving for blood and flesh.
After the conversation, Seimei continues her search and finally finds numerous spikes.
She is about to return to the Tree: Manor, when Doman attacks her inside the Lab. He tells Seimei that her body would be a lovely cocoon. After the short conversation, the final showdown begins.
Seimei uses all of her strength and defeats Doman. Dying, he stated that if only he had completed the Kuon spell quickly, his death wouldn’t have happened. Doman’s real intention in performing the ritual was to defeat Seimei. Utsuki then appears behind Seimei, loses herself and abducts the body of her own father and enter the chest with his corpse.
After sealing the Mulberry Tree, Seimei has no choice but to destroy the chest where Utsuki enters, since they don't know what kind of creature will emerge from it. Sakuya stops her and explains that Utsuki has never seen the outside world because her father tricked her. Seimei calls her a stubborn child and gives Sakuya the spikes "just to make sure". Seimei then leaves, leaving Sakuya with the chest and spikes along with the dead bodies of the twins.
- Abe no Seimei is based on the historic figure of the same name, the legendary Onmyoji from the Heian Period and the rival of Doman Ashiya. However, the historical figure Seimei is a male.
- The Summon Cards: Zenki and Goki, are considered by as a rare and the strongest cards in the game.
- The name Seimei means "Life and Existence".