Shōnen Onmyōji is a light novel authored by Mitsuru Yūki with illustrations up to volume 47 done by Sakura Asagi, and by Itō Natsuo from volume 48 onward. The novel is serialized in Kadokawa Shoten's The Beans and currently has 54 volumes, including short stories and side stories.
A manga adaptation of the light novels was later produced, written by Hinoko Seta and published by Kadokawa Shoten in the magazine Monthly Asuka. First published on August 25, 2005, the manga is ongoing.
A further anime adaptation titled Shōnen Onmyoji: The Young Spirit Master, was later produced as well. Created by Studio Deen under the direction of Kunihiro Mori, the anime ran from October 3, 2006, to March 27, 2007, spanning 26 episodes.
The plot of all incarnations is set in the Heian era of Japan and follows Abe no Masahiro. He is the grandson of the great onmyōji, Abe no Seimei, though Masahiro lacks the ability to see spirits. The series follows Masahiro's quest to overcome being trapped in the shadow of his grandfather's image while fulfilling his promise to protect Princess Akiko of the Fujiwara clan and stop the hordes of demons invading Japan.
Tropes associated with this work:
- Action-Hero Babysitter: Guren took care of Masahiro when he was young.
- Ax-Crazy: Kyuuki and his minions.
- Badass Adorable: Masahiro, Mokkun, Taiin, and Genbu.
- Berserk Button: If you ever try to hurt Masahiro.... you better run away, because Guren will totally kick your ass.
- Don't call Masahiro "Seimei's grandson", either.
- Same goes to calling Mokkun a mononoke.
- Big Brother Mentor: Narachika is this to Masahiro.
- Bittersweet Ending: Masahiro manages to save the world and Guren...but at the cost of Guren's memories of all the time they had together. Permanently. In the novels Masahiro loses his spiritual sight in the same incident. Guren recovers his memories a novel later, and Masahiro regains his spiritual sight, but not until the end of the story arc.
- Cerebus Syndrome: You thought the whole episode with Guren losing his soul and having to be mercy-killed (He Gets Better) was bad, come the latest arc, Narachika is probably dead, Masahiro has less than two years to live in a non-negotiable mandate by the heavens, Akiko has accepted that she will never be able to be together with Masahiro, and as usual, Kyoto is overrun by demons. Phew.
- Cry into Chest: Masahiro does this in the novels when he and Narachika are reunited after the battle with Ryuusai.
- Dark and Troubled Past: If anything, Guren's should count. Really most of the shikigami count due to their long lives and constant dealings with demons. Masahiro's, too.
- Damsel in Distress: Akiko is kidnapped by demons at one point so they can use her blood to revive their master. This triggers a rescue attempt from Masahiro.
- The Determinator: Masahiro, Guren, Kazane, and many others.
- Guardian Angel: Guren acts something like this towards Masahiro, whom he's sworn to protect.
- Famous Ancestor: Masahiro is the grandson of the famous onmyōji, Abe no Seimei.
- Fiery Redhead: Guren.
- HeelFace Turn: Kazane
- I Can Still Fight!: Masahiro uses this a lot.
- In-Series Nickname: Masahiro is "Seimei's Grandson" and Guren is "Mokkun" (and sometimes "Touda"). Touda is his original/true name; Guren is the name Seimei gave him.
- Jerkass: Fujiwara no Toshitsugu, though he gets better.
- Jerkass Has a Point: Fujiwara no Toshitsugu thought Masahiro was using his family's prestige to wriggle out of his job. Which is a bit rich (badum-tss) coming from a member of the Fujiwara Clan
- Kid Hero: Masahiro, though he is officially an adult by Heian standards. As of the current volume he has turned 18, and thus is actually more-or-less an adult.
- Morality Pet: Masahiro was more or less this to Guren.
- Ridiculously Cute Critter: The Hyakki-yakou.
- The Legions of Hell: A whole bunch of demons are invading Heian-era Japan.
- Older Than They Look: Seimei's twelve shikigami.
- Parental Favoritism: Masahiro seems to be a bit favored over his brothers due to his talent.
- Poor Communication Kills: Oh lordy, Guren is mind controlled by Ryuusai and almost maims Seimei against his will. Once he snaps out of it, the shikigami come and...assume Guren attacked him on purpose, not even giving him time to clarify/explain the situation! This would have been avoided if they didn't jump to conclusions and actually let Guren talk!
- The Resenter: Masahiro's older brothers are more upset with the Parental Favoritism than they show. But in this case they are resented only with the situation and both of them really care for Masahiro and love him.
- Stepford Smiler: Masahiro after Guren loses his memories of him. He tries to endure it but he breaks down when his brother comes to visit him.
- Yandere: Fujiwara no Keiko. Going as far as offering herself to demons over love counts.
- Youngest Child Wins: Masahiro is the both the youngest and most powerful of all his siblings.