Psychic Detective Yakumo (or Shinrei Tantei Yakumo) is a series of novels by Manabu Kaminaga.One day, college student Haruka Ozawa's friend Miki goes on a test of courage with a friend at a building said to be haunted. Suddenly she loses consciousness for no apparent reason, and must be admitted to the hospital. Due to the suspicious circumstances, Haruka decides to enlist the help of the cynical, sarcastic Yakumo Saitou, a supposed psychic. After realizing he's a fraud when it comes to having psychic abilities, he reveals that he can see ghosts, and will assist her. During the investigation, they get attacked, and it turns out his left eye is red, and that this is the eye with which he can see ghosts.The series has spawned two manga series (one by Miyako Ritsu, subtitled Akai Hitomi wa Shitteiru [The Red Eye Has a Clue] [completed], one by Oda Suzuka [ongoing], who is the character designer for the anime as well), a live-action drama, a stage play, and a Thirteen Episode Anime series by Bee Train.No relation to Yukari Yakumo.
Animal Motifs: Yakumo resembling a cat when he's sleeping (and a caterpillar when he's in his sleeping bag), and Gotou resembling a bear.
An Astral Projection, Not a Ghost: In the midst of all the actual ghosts, one apparent ghost turns out to be the projected spirit of a terminally ill but still-living girl, whose anxiety about her impending death causes her to project her spirit to other people at night while she's sleeping.
Bishounen: Yakumo. Also a good amount of the other male college students that pop up.
Curtains Match the Window: Yakumo, when he has his contact lens on. Haruka in the Ritsu/Suzuka mangas and novels, but not the anime.
Fire-Forged Friends: Yakumo and Gotou use each other for the common goal of solving cases. Yakumo uses the information Gotou possesses as a police detective, while Gotou uses Yakumo for his ability to see the dead.
First Name Basis: In both manga versions, Yakumo tells Haruka to call him by his first name so it would less of a hassle. In the anime, she starts calling him "Yakumo-kun" on her own, much to Yakumo's initial chagrin.
Freakiness Shame: When Haruka discovers Yakumo's red eye after he wounded from an attack, Yakumo tells her she must be disgusted (in the Ritsu version) or thinks that she would scream (Suzuka version). Instead, Haruka is the complete opposite and reassures him of it. She even thinks it's "pretty."
He Is Not My Boyfriend: Yakumo and Haruka are often mistaken for a couple. At one point in the Ritsu manga and the anime adaptation, Haruka denies that Tatsuya is her boyfriend.
Heroic Self-Deprecation: Yakumo and Haruka. Yakumo feels he can not help others and can only "see" using his red eye, while (in the Ritsu manga adaptation) Haruka feels she can not help others in spite of so many people helping her.
Knight in Sour Armor: Yakumo is one of these. He's always got a rude, sarcastic remark for everyone, but he still assists the police department in solving murder mysteries.
Limited Wardrobe. Come on, a female college student who wears the same outfit everyday? It's even weirder than the ghosts.
At least she finally changed in the last anime episode for Isshin's funeral. Everyone did, actually.
In the novels, we often get updates on what she's wearing when the story is told from Ishii's perspective.
Love at First Sight: In the Suzuka manga version and anime adaptation, Ishii sure seems a bit smitten with Haruka. In the former, he even thought she was an angel.
Make It Look Like An Accident: This happens to Yuuichi/Kazuhiko (in the Ritsu version and Suzuka version, respectively)'s murder, which is supposed to look like suicide, and to the ghosts' murders in the Dark Tunnel plot in the Ritsu manga.
Meaningful Name: Mentioned in the Ritsu manga adaptation and the anime, Yakumo means "multicolored clouds."
Parental Abandonment: After attempting to strangle him, Yakumo's mother disappeared. We also don't know what happened to his father. In the anime, his father turns out to be the silver haired antagonist that's been trying to provoke Yakumo, and his mother is revealed to have been Dead All Along.
Psychic Powers: Yakumo isn't literally psychic, but he can see and communicate with the dead.
Red Eyes, Take Warning: Yakumo's left eye is red and allows him to see ghosts. Yakumo's uncle wears a red contact lens to match Yakumo's left eye in order to understand him a little more and share his burden. And the mysterious silver haired antagonist who is revealed to be Yakumo's father from the anime adaptation.
Sacrificial Lamb: It varies between adaptations. In the Ritsu manga version—Yuuichi and Shiori, in the Suzuka version—Kazuhiko, and in the anime adaptation—again, Yuuichi. In a way, it's easy to sympathize with Haruka, considering that all these people are her friends.
Unfinished Business: This is why ghosts are attached to the human world and cannot move on. They cling onto feelings, whether it's the desire to be avenged (The Locked Door / Closed Door arc) to the desire to live (The Dark Tunnel arc) to genuine feelings for another (Ayaka's desire to watch over Haruka and the Message to the Dead arc, specifically Shiori's feelings of guilt for involving Haruka in her murder.
You Wake Up in a Room: When Takaoka-sensei (in the Ritsu version) / Yuuichi (in the Suzuka version) thinks he killed Yuri after hitting her a little too hard, he hides her body in the basement. Turns out she wasn't dead after all. Until she died trying to get out of the room.
Miyako Ritsu Manga Series
Armor-Piercing Slap: Haruka delivers one to Tatsuya in the Ritsu manga when it's clear that, in spite of being the culprit for an accidental hit-and-run murder, he's only considered for his own welfare, triggering Haruka's memories of her late sister.
Heroic BSOD: Haruka goes through one of these when she finds out that Shiori is dead. Averted big time with Tetsuya, who is unable to see the wrong in his actions, even after getting slapped by Haruka.
I Never Said It Was Poison: Haruka realizes that Takaoka-sensei murdered Yuri Shinohara when he mistakenly asked who Haruka thinks murdered Yuri, as there was a lack of evidence as to identity how the victim died or if the victim died (as Yuri's body hadn't been discovered yet).
It's All About Me: Tatsuya. According to Yakumo, he's inconsiderate for always only thinking of himself and what solely affects him. And if anything doesn't go his way, he'll just laugh it off. As it turns out, Yakumo is completely right.
It's Personal: For Haruka in the Message From The Dead arc when her friend Shiori is killed.
Meganekko: Yuri Shinohara was one in the Miyako Ritsu manga.
The Nicknamer: Yakumo often calls Haruka a "busybody" for always trying to solve other people's problems.
Not What It Looks Like: After Haruka goes to Yakumo's place to consult him on seeing a ghost in her apartment, he starts taking off his shirt to change into a warmer one. Gato happens to pick that time to drop in on Yakumo to ask him about a case. Subverted in that Gato knows it's not what it looks like and is simply the Shipper on Deck for Haruka and Yakumo.
Teacher/Student Romance: In The Locked Door arc, Yuri Shinohara had an affair with Takaoka-sensei and threatened to tell his wife.
Wrong Genre Savvy: In the Ritsu adaptation, Tatsuya thinks Yakumo dislikes him because he's "close friends" with Haruka. Yakumo just doesn't like him (especially after Tatsuya unintentionally "disrespected the dead" in Yakumo's perspective by thinking a ghost was killing people in a discriminable way).
Oda Suzuka Manga Series
Genius Sweet Tooth: Yakumo. This is lampshaded in the Oda Suzuka series, where after interrogating the ghost possessing Miki, he needs to rest a while. It cuts to him eating ice cream at a cafe, with his excuse being that after "being forced to use his head", he needs sugar.
Teen Pregnancy: In the Oda Suzuka version, where Yuuichi is the culprit of The Closed Door arc. He indirectly killed Yuri Shinohara following a fight because she got pregnant.
Adaptation Distillation/Adaptation Expansion: Plot elements of the manga arcs have been shortened or cut out to fit the thirteen episode series, and some character roles have been changed or added in. For example, Tatsuya is a co-worker of Haruka's instead of an aquaintance she met at Miki's party.
Adults Are Useless: Haruka's mother seems strangely fine with sending her daughter into what could be a dangerous situation. She barely puts up a fight to talk her daughter out of it.
Break the Cutie: Implied with Yakumo's mother, who was revealed to have been kidnapped by Yakumo's father and was impregnated by him. The antagonists attempt to do this to Haruka in order to break Yakumo, but Shunsuke Takeda protects her.
Captain Obvious: Doctor Sakakibara, upon seeing Haruka and Detective Gotou, runs away from them. They had never met him before, but Gotou chases him anyway.
Not to mention Nanase Miyuki's singing a whole verse of London Bridge is Falling Down.
Green-Eyed Monster: Haruka was a little saddened to see Yakumo with another girl in the second episode, but as it turns out, the girl was the client who had asked him to investigate the episode's ghost.
Jerkass: Yakumo is a bit more of a cocky jerk in the anime adaptation than its manga counterparts.
Lighter and Softer: Certain episodes—such as The Locked Room arc and The Dark Tunnel arc from the Ritsu manga adaptation—based on the manga arcs have been altered to a degree (thanks in part to the fact that the anime will only have 13 episodes), but nevertheless some of the twists in the anime are much more lighter compared to its manga counterparts.
Memento MacGuffin: Seemingly the red gemmed necklace that Yakumo always hold onto. It belonged to his mother. He later lets Haruka hold onto it.
Mistaken for Gay: Yakumo hilariously convinces Gotou that Ishii has a thing for him. Ishii doesn't; he just loves the occult and thought Gotou was a psychic detective instead of Yakumo. And he actually has a thing for Haruka.
A self Shout Out in episode 8. Makoto holds a card with the words D-Station written on top. D-Station is a subdivision of Bee Train the studio that animates the series. Besides the name, even the address is the same.
One takes place in episode 12. Read the quote, then no further explanation is needed:
What Happened to the Mouse??: We're not shown what happens to Tatsuya in the end of third episode, but it can be assumed he'd been arrested for the hit-and-run. The Ritsu manga adaptation, however, sheds a little more light on this.