[[caption-width-right:332:Pictured: [[DudeLooksLikeALady Karyou Kaie]]]]

DDD. Decoration Disorder Disconnection. A set of novels by [[Franchise/{{Nasuverse}} Kinoko Nasu]] that explores the notion of "DemonicPossession". No direct connections to the rest of the Franchise/{{Nasuverse}} yet.

In a certain part of Japan, there is a syndrome known as Abnormal Agonist Syndrome. A bizarre illness that blurs the line between physical and mental, it usually only affects people who are already in a sorry state - people who are suicidal, paranoid, abused, and so on. Infectees at best end up with incomprehensible thought processes and at worst go completely, utterly insane. Oh, and they also tend to gain superpowers and horrifically altered bodies. These psychosis and powers are tailored to whatever caused them to develop AAS in the first place - take for instance, the suicidal StarterVillain Kizaki. Physically, he gained a neck capable of rotating 360 degress and the ability to force people who have looked into his eyes to mimic his actions, while mentally, he became completely disconnected from the world and simply sat in front of his mirror endlessly rotating his neck, convinced that he was breaking it and would soon die, and was totally unaware that he was causing anyone nearby to kill themselves.

Of course, the general population doesn't really know this. As for as most are concerned, what's actually happening is that people are being possessed by demons.

All of this takes place in Shikura City. To combat this outbreak, the city government has made the Origa Memorial Institute the main hospital for anyone affected by AAS.

Also, the real demons are a little bit upset by these people stealing their thunder. Well, technically, demons aren't real. Neither are what most Agonists turn into. It takes something unreal to fight something unreal. Confused yet? Yeah, this series will do that.

Arika is a survivor of an Agonist attack (by his sister Kanata, as it happens) with one arm who is considered both rather harmless and one step away from being an Agonist himself. He was kept in Origa for a couple years while the doctors there examined him to make sure there were no lingering issues. Slightly odd, he'll comment that one should never tell him anything serious during daylight hours, and nothing silly at night - this is because he has a strange mental defect that causes him to lose all his memories of the day at nightfall, and as such, he can only remember things that happen to him at night. He is employed by a rather bizarre and sadistic yet beautiful boy named Kaie Karyou, who claims to be a "Demon Master." His only job is to put on and take off Kaie's prosthetic limbs, something for which he is paid 200,000 yen ($1600) per month.

Two volumes are compiled and there is a side story called "3/16 Incident: Outside the Universe". There is supposed to be a third volume, but there's no word on when it will come out.

[[http://forums.nrvnqsr.com/showthread.php/2637-DDD Here's an online translation]].

!!DDD provide examples of:

* ArtificialLimbs: The prosthetics of Karyou, [[spoiler: which are ''true'' demons. He occasionally loans one out to Arika, whose arm was eaten off by his sister.]] Arika notes that, before coming into contact with Kaie, he tried several, but each one caused severe phantom pain.
* BackToFront: The entire first volume.
* BadassNormal: Touma has no traits that set her above normal humans (apart, yes, above, no), yet still managed to beat Kanata in a fight.
* BerserkButton: Calling Mato Touma 'Tomato' is... not wise.
* BloodSplatteredWeddingDress: What Kanata was wearing when she first became 'possessed.' The blood came from killing her parents, by the way. ''Why'' she was wearing it is still unknown.
* BodyHorror: Some Agonists become....nasty looking.
* CameBackStrong: One of Kanata's powers. Every time she dies, she resurrects later completely immune to whatever killed her. Thanks to experiments run by the doctors at Origa, she's basically invincible at this point.
* CognizantLimbs: All of Kaie's prosthetic limbs are living, shapeshifting demons.
* CollectorOfTheStrange: Kaie collects prosthetic limbs, which are also demons. He's known to have at least eight, but is implied to have far more. Less strangely, although still pretty odd, Tsuranui collects old cell phones, which she claims she plans to use to build a robot.
* DemonSlaying: Arika at night and with the Arm of Hatred.
* DrJerk: Touma is actually a genuine medical doctor, and very good at it. She is also the exact opposite of a nice person. Her doctorate doesn't come up much, because by the time most of the story takes place in, she's busy with being a police officer and punching out monsters and all that.
* DudeLooksLikeALady: Karyou Kaie
* TheDreaded: Everyone who knows Kanata Ishizue is flat-out terrified of her (with the exception of Touma). Arika in particular would rather do even the most absurdly dangerous and life-threatening things than risk running into his sister.
* EverythingsEvenWorseWithSharks: Sorrow, one of Kaie's demons, takes the form of a shark when it's not being his leg.
* {{Expy}}: Karyou is very similar to Merem Solomon of ''{{VisualNovel/Tsukihime}}'' in terms of situation. In terms of story role and character, he and Mato are essentially [[KaraNoKyoukai Touko Aozaki]] split into two characters.
* TheFool: Tsuranui is very out there and wanders unknowingly into danger with astonishing regularity. And yet, somehow, by sheer luck, she's always fine.
* FriendOnTheForce: Touma is this to Arika.
* GenkiGirl: Tsuranui fits the trope to a T. She occasionally seems to be trying to be a ManicPixieDreamGirl to Arika, but she keeps getting shut down.
* GunNut: Touma is known to own at least three handguns, a shotgun, and a rocket launcher. She also dreams of one day running a shooting range and self-professes to love guns.
* HollywoodAcid: Yukio Fusou's powers revolve around her ability to secrete an incredibly corrosive acid that can apparently eat through just about anything - even weapons being used against her.
* HunterOfHisOwnKind: Shusei Hinomori is an Agonist dedicated to eliminating all other Agonists. Since he managed to draft Makina Hisaori into helping him, that makes her one too.
* ImAHumanitarian: Several Agonists, most notably Yukio Fusou.
* LemonyNarrator: Arika.
* MorallyAmbiguousDoctorate: Touma may not be evil, but one still questions how someone so violent, harsh, and generally mean managed to become a medical doctor - and ''stay one''.
* MyBloodRunsHot: Kazumi Iguruma has the power to ignite his blood. It acts more or less like jet fuel, propelling things at high speeds in various directions. He uses it to make impossible pitches and kill people with thrown baseballs.
* MysteriousStranger: A ragged-looking man in a grey suit claiming to be possessed by a demon has been seen a couple times. He's known to have caused at least two people to develop Agonist Syndrome, he once entered Karyou's residence then disappeared, and his name is apparently something very common yet no one can remember it. Aside of that, nothing at all is known about him.
* MythologyGag: Arika mutters to himself that only an idiot burglar would go to the police if they discovered the family they're robbing was murdered. This happened in ''LightNovel/KaraNoKyoukai''. Arika isn't one for compassion.
* NoSenseOfHumor: Arika is convinced that Mato doesn't have one, at any rate.
* NoteToSelf: A necessity for Arika. Whenever night falls, he forgets everything that happened between sunrise and sunset, and as a result, he's taken to carrying around a notebook to record the events of the day in.
* OnlyKnownByTheirNickname: Tsuranui's real name is Mihaya Kinui, but you'd be forgiven for not knowing that, since it's almost ''never'' mentinoed.
* OurDemonsAreDifferent
* PhysicalScarsPsychologicalScars: An unusually direct case. Arika directly connects the loss of his left arm to the loss of 'part of his soul.' That part that was capable of feeling threatened, apparently. This may have something to do with ''how'' he lost his arm, and ''what'' he lost it to.
* PoliceAreUseless: Sort of. The police force in Shikura don't have the means/gear to take on anyone affected by AAS. With the exception of Mato Touma, who seems to be able to take them down through sheer determination and badassery. And guns. Lots and lots of guns. Arika notes that the police would be able to take on the 'demon-possessed' pretty easily if they could get proper arms.
* PowerBornOfMadness: Agonist Syndrome, all the way.
* SunglassesAtNight: Shusei does not take his sunglasses off, ever. Even while fighting a dangerous Agonist late at night.
* SupernaturalGoldEyes: Arika's sister, Kanata, has this. She earns them; as she's one of the most powerful and insane of the Agonists.
* TooSpicyForYogSothoth: Hatred and Sorrow recoil in fear when Mato Touma enters the room.
* WhereTheHellIsSpringfield: Shikura City's location is not mentioned so far, except it's in Western Japan.