In World War II the Japanese military approached the genius onmyoji Yakou Tsuchimikado, seeking new weapons to further the country's ambitions of becoming a world power. With their resources he was able to rewrite the book on magic, creating a modernised form of Onmyodo with incredible power. Yakou was regarded as a hero or even a figure of worship... until he brought about the Great Spirit Disaster in Tokyo during a Last Stand to avert Japan's defeat. While Yakou died in the Disaster, magic and Magitek derived from his teachings are still in use today.Harutora Tsuchimikado comes from a branch of the same prestigious family as Yakou, but his ability to detect spirit energy is zero. Since he has no interest in becoming a proper onmyoji nor obligation to do so, he's been enjoying a peaceful daily life with his friends at a normal high school. And then one day his childhood friend Natsume Tsuchimikado, heir to the head family, suddenly appears...A manga adaptation is currently running, while an anime adaptation aired in October 2013.
The Dark Arts: Imperial-style Onmyodo, the original version of Yakou's techniques from before the civilian curriculum was developed. Most, but not all, of its spells are banned for being too dangerous or destructive or for being related to soul manipulation.
Death Is Cheap: Averted. Several characters get revived. But not one has come back as a human...
Deconstruction: The story deconstructs the role of magic in society and its lack of domestic benefits. Its only use is combat and exorcising spiritual disasters caused by Yakou's failed ritual and spiritual terrorism.
Dramatic Irony: Natsume is the controller of the operation-type shikigami Hokuto, this means that the Hokuto Harutora knew was actually Natsume, but Harutora is too dense to figure it out. At least initially.
Earn Your Happy Ending: Subverted in a very heart wrenching manner. Near the end of volume 10 Natsume races to Seishuku branch temple to reach Harutora whom she hasn’t seen in a year. She clashes with Hayato Yamashiro and Tsuchigumo warriors using the power that sustains her life and nearly dying as a result. Before Natsume reaches Harutora, he senses her presence. And leaves.
Empathic Environment: Inverted. Fireworks popped in the background while a captured Harutora is forcefully kissed by Suzuka in-front of his love interest, Hokuto (the girl), and continue to pop when a teary Hokuto runs away. Again, fireworks popped in the background when Natsume sacrificed her life to save Harutora after the Raven Coat reacted with his power.
Familiar: Shikigami; there are different types. In general, we have:
"Simple" Shikigami, which can be anything ranging from vague figures to animal-shaped to full-on human-like constructs. Typically, they perform only the basic commands and functions for which they were intended, or are outright-used as remotely-controlled puppets. Their vessels are always typical shikigami charms, since they are not that complex compared to the other types. note Examples of this type include the various black figure shikigami seen used to move things, the general-use shikigami used by the Magical Investigators and Ohtomo,Natsume's male-version of herself, and girl-Hokuto.
"Mechanical" Shikigami, named not because they are made from machines or so, but because their vessels are typically not shikigami charms, but various tools charged with magic or outright magical shells that act as their bodies. Depending on the shikigami, they have varying grades of awareness and ability to act independently. note Examples include the Ashura used by Suzuka at the start of the series and the Onmyo Academy gatekeepers Alpha and Omega.
"Defense" Shikigami, the strongest type and the most taxing on the user, since they are more-or-less always active and constantly draining the user's magic reserves. The drain is usually not a problem when they are not physically manifested in the real world, but can be quite taxing on the user once they do. These range from especially-made artificial shikigami with both the ability to be controlled remotely and with the ability to act independently, to living, breathing beings which take the form of various mythological figures and creatures. These latter ones are explained as beings suddenly coming into existence or awareness through items that possess great amounts of magic power. note There's tons of these in the series, like Natsume's dragon Hokuto,Kon, Yakou's Hishamaru and Kakugyouki and Kyoko's Kakfu and Hokfu. Harutora himself is technically one of these to Natsume.
Famous Ancestor: Tsuchimikado Yakou is the ancestor of Harutora and Natsume, and Abe no Seimei is another one of their ancestors further back.
Firing One-Handed: Averted in the anime with Magical Crime Investigatorsnote mage police, they use both hands when using handguns. Played straight with Hirata Atsune because he is actually a teenager in disguise.
Flash Step: Spirit Step, an Imperial Style spell that Reji Kagami performs during the Chimera Incident. It uses spirit pulses to move from one location to the next instantly.
In the early episodes, Hokuto (the dragon) responds to Harutora calls.
When Natsume names her remote body shikigami Hokuto (the girl) who is really her after the dragon Hokuto.
When Suzuka hugs an one eyed tiger plushie with an bandaged eye.
Episode 9 When Hirata is performing the Taizan Fukun Ritual then giving thanks to the dead Mutobe.
Touji is seen walking out of Shamanic/Onmyo Clinic in the first episode.
Episode 2 has a pretty subtle one: during a history lecture on prominent Onmyouji, on blackboard lists the names and info of Abe no Semimei and Douman Ashiya are displayed. However only a birthdate and deathdate is shown for the former...
In Light Novel & Manga: When Ohtomo first meets Kon he notes that she has a seal on her, this mentioned again by Suzu Saotome.
In Episode 6 the camera pans to Kon as Kakugyouki comments on Hishamaru.
Gone Horribly Right: The Tsuchigumos developed by Yakou Tsuchimikado for the army were used to wipe out a group of Magical Crime Investigators and Kill the Cutie. Douman also used imitations of them to attack Omnyo Preparatory School and the Onmyo Agency.
The Tsuchimikados' plan to hide Harutora's identity as the true reincarnation of Yakou. They were doing quite well, Natsume's life-long burden aside, until the secrecy made an inconsistency apparent when Kyoko unwittingly revealed it to Takiko...which lead to the latter acting rashly, Harutora suffering Power Incontinence, and Natsume getting killed saving Harutora from it.
For that matter, Takiko's rash plan to awaken Harutora as Yakou. It was a complete and utter success. Not only did Harutora awaken, after a while so did Kon as Hishamaru, and even Kakugyouki returned to him as well. It also got Natsume killed, broke the main cast's fellowship, got Harutora branded a terrorist, and completely destroyed the ancient friendship between Yakou and the olden Kurahashi and Souma clans that she so desperately wanted to revive and protect. GJ, Takiko.
Government Agency of Fiction: The Lingering Spirit Division in the Imperial Household Agencynote Responsible for stabilizing the spirit flow in Tokyo and exorcising lingering spirits which were predominantly nobles and royalty. This Agency became a nest for Yakou fanatics due to the nature of the work and was purged prior to the beginning of the story.and The Onmyo Agency.note Includes the Exorcism Bureau to handle spiritual disasters and the Magical Crime Investigation Bureau.
Gratuitous English: Rather than something traditional like "Kyu-kyu nyo ritsu ryo"note Roughly "Heed this command swiftly", a phrase originally used to end government decrees, the trigger command for modern onmyodo spells is "Order!".
Guns Are Worthless: Averted as they show up in the hands of the right people despite the fantasy setting, who are not afraid of using them and the bullets hurt and kill people. Played straight against any of the top Onmyoji.
Hell Gate: Pretty much what spiritual disasters do and are: gradually damage the surrounding area, growing in power, manifesting physically as "demons" and monsters, and eventually becoming a huge mess of out-of-control spiritual energy that keeps creating more spiritual disasters to start the cycle all over again.
Instant Awesome, Just Add Dragons: Natsume's shikigami is a large dragon named Hokuto. It's called one of the few remaining "true dragons", whose auras are entirely Yin aura, which is why they also happen to make excellent bait for mobile spiritual disasters.
I Surrender, Suckers: What Daizen Amami does to take down the mole, Takiko Souma disguised as Hirata.
Kissing Cousins: Harutora and Natsume. Technically, what Kyoko wants with Natsume—before learning Natsume is actually a girl. Then it's with Harutora—, since the Kurahashi clan is a Tsuchimikado branch family that separated generations ago.
Leaning on the Fourth Wall: If you watch the bottom-right hand corner during the principal's lecture on Yakou in Episode 4, the corner reveals a person looking back at the camera.
Natsume is in love with Harutora, who admits to having feelings for Hokuto, or rather, the person who controlled her vessel, who happens to be Natsume. Harutora doesn't realize any of this until later.
Kyoko is in love with Natsume (not knowing Natsume's actually a girl), with whom she made a promise in their childhood the one day they spent together to find and return to her a ribbon Kyoko's grandmother made for her. She actually made that promise with Harutora, but she never asked his name when they were together. note She assumed he was Natsume after asking her grandmother for the Tsuchimikado heir's name, and so assumed she made the promise with Natsume, which is the basis for her feelings for Natsume at the start of the series. Natsume herself was sick that day, which is why Harutora was on his own when he and Kyoko met. Once Natsume's real gender comes out, Kyoko realizes the misunderstanding and her feelings shift to Harutora.
Suzuka developed a crush on Harutora because of his compassion for her and forgiving her for "killing" Hokuto, the event that is the reason part of her feelings were driven by guilt. That, and because he was her first kiss. Her feelings only grow because of the several times Harutora attempts to cheer her up and make her acknowledge that she doesn't have to be alone.
So, to summarize: Suzuka likes Harutora. Kyoko likes Natsume then later likes Harutora, who likes Harutora, who likes Hokuto, who's also Natsume. Kon likes Harutora because Kon is Hishamaru, who likes Yakou, who is also Harutora.
Lowered Monster Difficulty: The first time a Tsuchigumo is seen, it defeats a group of professional Onmyoji with ease. The second time they are deployed en mass by Douman and are held back by a group of Onmyoji students. Justified in that they were imitations that lacked solid vessels.
Mistaken for Gay: Both Harutora and Natsume are mistaken, when Natsume's male double shikigami (long story) undresses while in Harutora's embrace. The Girls LOVE IT.
Then comes the Dougenzaka mess, where the past incident's misunderstanding comes up again. They manage to shake off the homosexuality suspicion...but Harutora accidentally lands himself an even worse label: Lolicon.
Mistaken Identity: Harutora is sometimes mistaken for Natsume. This is mostly due to Natsume pretending to be a boy. The reason Kyoko even likes Natsume is because she got Natsume mixed with Harutora as children and really fell in love with him.
Moment Killer: Suzu Saotome showing up right before Natsume is about to confess to Harutora.
Sacrificial Revival Spell: The Taizan Fukun ritual, supposedly. The version used by Suzuka is actually one of several versions, and there are ways to use it to successfully revive someone without need to sacrifice one's life.
¡Three Amigos!: Harutora, Touji and Hokuto in the first chapters, then its Harutora, Touji and Natsume, mainly. Bonus points for essentially being made up of the same three characters. This trio also forms part of the main cast alongside Kyoko, Tenma and Suzuka.
Later, they discover that Jin Ohtomo, Zenjirou Kogure and Suzu Saotome were a similar trio.
Wholesome Crossdresser: Harutora had a date with one. Harutora thought that the crossdresser was a girl and was greatly disturbed when he found out.
Also Natsume, thanks to a main family tradition that states the heir must present themselves as a male in relationships with outsiders, which she took at face value.A FAKE tradition that Natsume was told about in order to hide that Yakou's real reincarnation, who was born male, is not Natsume, but actually Harutora.