[[quoteright:200:https://static.tvtropes.org/pmwiki/pub/images/koineko.png]]

''Koi Neko'' is a RomanticComedy {{seinen}} manga by Mashima Etsuya, which was serialized in ''Sunday Gene-X'' from 2004 to 2012 and compiled into 12 volumes.

The manga tells the story of Shinta Takaoka, an [[OrdinaryHighSchoolStudent Ordinary Middle School Student]], and his girlfriend Nao Sakurazaki... who happens to be a CatGirl... and the [[UnwantedHarem other girls vying for his affection]], several of which are {{Cat Girl}}s as well. HilarityEnsues as [[ClingyJealousGirl Nao]] tries to seduce the chaste Shinta while fending off his other would-be-lovers.
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!!This series provides examples of:

* AbusiveParents: Shinta's mother shows no mercy if she catches him [[NotWhatItLooksLike in a compromising position with Nao]] or hears one of Nanami-sensei's heavily embellished and exaggerated reports.
* ACupAngst: Nao angsts over her small chest in comparison to [[BuxomBeautyStandard Wakaba's massive bust]].
* AlternateSelf: Nao has a dream where she is in a world where Shinta doesn't exist, and meets a melancholy version of herself with short hair. [[spoiler:This short-haired Nao shows up in the final two arcs, having crossed the boundary between worlds as a [[OurGhostsAreDifferent Fragment of If]] to confess to Shinta. It turns out she is Nao's deceased sister, resurrected by Inaho for the purpose of fulfilling their wish.]]
* AngstySurvivingTwin: The long-haired Nao had a twin sister who died when she was a kitten and is buried at Inaho's temple. While she doesn't angst about it early on due to not remembering much from that time, she becomes melancholic about it in the last few chapters. It's strongly implied that [[spoiler:the short-haired Nao is either the sister's ghost or from a universe where she lived but the long-haired Nao didn't]].
* ArentYouGoingToRavishMe: Nao and Miyabi frequently find themselves asking Shinta this.
* AsianFoxSpirit: Inaho is a kitsune in the service of Inari and possesses a number of supernatural powers. She is also connected to a kitsune statue outside the shrine, and any damage to it is reflected on her and reduces her powers.
* BecauseYouWereNiceToMe: The reason most of the cats fall in love with a human. Shinta looked after Nao and her sister when they were children, though [[ForgottenChildhoodFriend neither remember this]].
* BeCarefulWhatYouWishFor:
** Nao subconsciously wishes Shinta was a cat, which Inaho temporarily grants not realizing who it belongs to or what it entails. Nao, not realizing what happened, is horrified to be reminded of her traumatic dream.
** The short-haired Nao wished to wait for Shinta forever, and is first met in an alternate universe where Shinta has disappeared, leaving her waiting for him for all eternity.
* BenevolentGenie: Inaho is a kitsune and servant of Inari, and she can use her divine powers to grant the wishes of others.
** [[HilarityEnsues Hilarity]] and CharacterDevelopment ensue when she decides to grant the wishes of the city's cats, which involves making Miyabi filthy stinking rich (and saddling her with Tora's babies, teaching her that money isn't everything), and turning Shinta into a cat.
** A more serious example is revealed in Chapter 91, where reveals [[spoiler:she previously granted the wish of a pair of dying kittens to see the little boy who cared for them again. One kitten died before the wish can be fulfilled, resulting in a complex Schrodinger's cat situation where the boy - Shinta - has to choose which Nao is the kitten who died and which is the one who lived, resulting in one of them disappearing]].
* {{Bifauxnen}}: Haru is assumed to be a boy due to her aggressive personality and the ShipTease between her and Miiko, making the [[UnsettlingGenderReveal discovery of her true gender a surprise]].
* BigEater: Miiko is constantly hungry and occasionally raids peoples' fridges for food.
* BoobBasedGag: Wakaba's large bust is the subject of several chapters' worth of jokes.
* CrazyCatLady: Wakaba is a full-on teenage version of this, and nothing will stop her from getting her kitty fix. She even has a [[SpiderSense Kitty Radar]] that lets her detect nearby cats.
* CallBack: When Inaho turns Shinta into a cat, [[RetGone everyone except Nao forgets about him and it's like he never existed as a human]], causing Nao to have a flashback to the Shinta-less dream-world when she met the short-haired Nao, who not-so-coincidentally makes a comeback in the arc.
* CatGirl: The Nao sisters, Miyabi, Miiko, and Haru are all cats who became able to transform into human form after falling in love with a human. Mikadzuki is a [[SpearCounterpart Cat Boy]].
* ChastityCouple: It took 19 chapters for Shinta and Nao to [[SacredFirstKiss even kiss]] (and Shinta was asleep at the time too), much to Nao's consternation. There ''have'' been times when Shinta's composure snapped, though.
* CurbStompBattle: When he starts regaining his repressed memories, Mikadzuki runs away and takes over a gang of cats in another neighborhood. When Nao and Miyabi go looking for him, Mikadzuki's new gang picks a fight with them. When Mikadzuki -- who had lost his memory of them -- shows up to fight them off, they mop the floor with him too and then take him home.
* CuteBruiser: Nao and Miyabi may look like 14-year-old girls, but they're a lot stronger than they look.
* DarkAndTroubledPast: When Mikadzuki confronts Inaho over the recent strange goings on, she tells him about Nao's backstory: A pair of newborn kittens were left in a box outside her shrine, and she waited for them to wish for food or warmth so she could use her divine powers to help them. When no wish came, Inaho found they were being looked after by a little boy. Just as she decided she was no longer needed and was about to go back to sleep, she felt the kittens wish to see the boy one last time, since the boy had been unable to come care for them and as a result they were dying. Before Inaho could grant that wish, she found that one kitten had already died and the other had been taken in by someone. With her powers weakened due to the little boy damaging one of the kitsune statues at her shrine while searching for the kittens, Inaho was only able to grant the dead kitten's wish -- creating the long-haired Nao and short-haired Nao in the process. With her power restored, she was able to create a Schrodinger's cat situation where the now-teenaged boy, Shinta, would be unwittingly forced to choose which of the Nao twins was the kitten that survived, and the other would disappear from existence.
* DeadAllAlong: [[spoiler:It's revealed that one of the two Naos died as a kitten and the other lived, but which it was isn't clear. Inaho's narration to Mikadzuki in Chapter 91 implies that the long-haired Nao - who wished to cuddle with Shinta forever - is the kitten who died and is buried behind the shrine, while the short-haired Nao - who wished to wait for Shinta forever - is the one that survived. To add to the confusion, UsefulNotes/SchrodingersCat is invoked, with Shinta unwittingly (at first) being forced to choose which of them was the twin who lived. In the end both of them live, so it ultimately doesn't matter which was which.]]
* DirtyOldMan: Of a comedic sort: Shinta's dad, Kazuya, is a lecher who keeps trying to SkinshipGrope his own daughter and is disappointed his son hasn't gone further with Nao, mainly so he could eavesdrop on them. However, he dishes out a few pearls of wisdom from time to time and [[HiddenDepths he's actually a famous author who wrote an extremely successful book based on his life]], but refuses to write a sequel until he's done raising his family.
* TheDitz: Nao comes across as this a lot of the time, not paying attention when being spoken to or getting confused by fairly mundane things.
* {{Foreshadowing}}: Mikadzuki's knowledge of the Cat's Song and of the amnesia that ensues when a transforming cat forgets about the one they love, which foreshadows the revelation that [[spoiler:he's a transforming cat himself]].
* ForgottenChildhoodFriend: Shinta took care of Nao when he was a child, although she was just a kitten at the time. Wakaba and Mikadzuki play this trope straighter, as he first took on human form when he was a kitten and she a child.
* ForgottenFallenFriend: Both Shinta and Nao have forgotten her deceased sister up until the final arc.
* ForcedTransformation: Inaho starts to turn Shinta into a fox as punishment for breaking off her tail as a child, though Nao requests she make him a cat instead. Shinta is later transformed into a cat when Inaho grants Nao's wish.
* FreakinessShame: When Inaho starts to turn Shinta into a fox and he sprouts whiskers and pointy ears, Nao finds it ''very'' sexy and offers him a place in the cat world, prompting Inaho to offer to turn him into a cat instead.
* TheGadfly: Nanami-sensei enjoys teasing Wakaba. She also likes putting Nao and Shinta into uncomfortable (for Shinta) positions, reminding them that they can't do anything romantic, and overreacting when Nao tries to do so anyway.
* HeadPet: Once Wakaba takes him in, Mikadzuki can be found lying across the top of her head.
* HollywoodToneDeaf: Nao's initial attempts to sing her Cat's Song can break glass. It's noted that she ''can'' sing, but trying to force her Cat's Song out without awakening it just isn't doing any favors.
* IdenticalTwinIDTag: In their cat forms, Nao and her sister were indistinguishable from each other. In their human forms, one has long hair in a HimeCut and the other has messy BoyishShortHair.
* InterspeciesRomance: Nao is a [[CatGirl girl who is a cat]] who fell in love with the human boy Shinta. And so is Miyabi, who fell in love with Shinta's grandfather 50 years ago. Mikadzuki, on the other hand, is a cat who is a boy who fell in love with Wakaba.
* IWantMyBelovedToBeHappy: Wakaba is a ShipperOnDeck for Nao and Shinta despite having feelings for him herself.
* JerkWithAHeartOfGold: Miyabi may act like a jerk at times, but deep down she's a good person.
* LaserGuidedAmnesia: When Inaho grants the long-haired Nao's wish to turn Shinta into a cat he loses all memory of her, but regains his memory and human form with help from the short-haired Nao. More generally, transforming cats whose loved one dies or disappears will slowly forget about them and lose the ability to transform. Additionally, if they state they hate that person they [[ShapeshifterModeLock are locked into cat form]] and lose all memory of the person they love.
* LittleBitBeastly: The transforming cats can assume a human form with cat ears and a tail.
* LovableSexManiac: Nao and Miyabi are constantly trying to get Shinta to sleep with them. The tomcats who hang with Mikadzuki aren't picky about who they flirt with, though they especially want Nao and Miyabi.
* MacGuffin: [[spoiler:The Naos' notebook ends up restoring Shinta's memory of them and returns them to existence.]]
* MagicMusic: The Cat's Song. Each transformed cat has a unique song in memory of the person they love, but can only awaken it through the heartbreak of forgetting about and regaining their memories of that person. The short-haired Nao and Miiko are shown singing theirs, Miyabi admits she has awakened hers, and it's strongly implied Mikadzuki has awakened his own as well. By the end of the manga, [[spoiler:the long-haired Nao awakens her Cat's Song as well]].
* MemoryGambit: As part of her arrangement with the Naos, Inaho messes with Shinta's memories so that he believes he's been dating short-haired Nao when it's her turn. Shinta gets the sense that something is wrong with the situation, but he nevertheless enjoys his time with them.
* OlderThanTheyLook: Miyabi is at least 50 years old, but looks 14 in human years and the same age as Nao as a cat.
* PlotAllergy: Shinta's father is allergic to cats, making his relationship with Nao problematic.
* {{Polyamory}}: [[spoiler:In the end, Shinta refuses to choose between the Naos and ends up dating both of them.]]
* PowerOfLove: What gives a cat the ability to transform into a human. If they say "I hate you" from the bottom of their heart, they lose their memories of the person they fell in love with and the ability to transform into a human with it. Regaining their memories and love of that person lets them transform again, and awakens their Cat's Song.
* PromotionToParent:
** Nao spends a chapter looking after a pair of kittens Shinta's sister found, and it only increases her desire to have children with him.
** When Inaho grants Tora's wish to be the father of Miyabi's kittens, she immediately divorces him but spends the rest of the arc doting on them and is heartbroken when they disappear when Inaho revokes her wishes.
* ReallySevenHundredYearsOld: Miyabi fell in love with Shinta's grandfather when he was 14, and still appears the same now as she did then. Conversely, Mikadzuki appears as an adult in human form despite having appeared to be the same age as Wakaba before. Nao tells Shinta that Inaho said their human form's appearance has something to do with their personality and emotions.
* {{Retgone}}:
** [[spoiler:When Inaho grants the long-haired Nao's wish for Shinta to become a cat, everyones' memories of him as a human - except hers - are erased.]]
** [[spoiler:Not wanting Shinta to be unhappy over having to choose between them, the Nao twins wish to disappear and have everyone's memory of them erased. Shinta's love for them restores his memory and he uses Inaho's magic box to bring them both back.]]
* RoofHopping: How the cats get around town.
* ShamelessFanserviceGirl: Nao has no compunctions about being naked in front of Shinta.
* ShipperOnDeck: Wakaba ships Nao and Shinta despite having feelings for him herself; Nanami-sensei ships Wakaba and Shinta.
* SternTeacher: Nanami-sensei is quick to jump to conclusions about the nature of Nao and Shinta's relationship, and -- being lazy -- enjoys hauling one or the other off to do work for her as "punishment" for violating the school's morals.
* StrongFamilyResemblance: Shinta looks similar to how his grandfather did when he was 14, which is why Miyabi initially falls for him.
* StrongerThanTheyLook: Nao looks like a scrawny 14 year-old girl, but can [[{{Roofhopping}} roof-hop]] with the best of them, and even carry Shinta while doing so.
* SurpriseIncest: The long-haired Nao has a dream where she reunites with the short-haired Nao, who kisses her on the lips rationalizing that [[ScrewYourself it's OK since they're the same person]] and because Inaho said it doesn't count when two girls kiss. [[spoiler:The short-haired Nao and long-haired Nao are later revealed to be twin sisters, though this doesn't bother them and they both end up dating Shinta at the same time.]]
* TheTease: Miyabi flirts with Shinta in a very suggestive manner both to see him get flustered and to get on Nao's nerves.
* ThoseTwoGuys:
** Tora and the other two tomcats who [[LovableSexManiac chase after every female cat they see]], especially Nao.
** Shinta's three male friends, led by Makoto Akidzuki, fill this role at school. There is also a trio of girls - Ryouko Aizawa, Hideko Kawamura, and Yumi Morishita - who are [[ShipperOnDeck rooting for Nao]].
* {{Tsundere}}: Midazuki becomes this for Wakaba as he slowly regains his memories of her. This is best-exemplified in Chapter 27, when he finally admits to himself he cares about her and regains the ability to transform into a human.
* UnwantedHarem: Shinta has Nao, Miyabi, and Wakaba all trying to be "[[UnusualEuphemism mellow mellow]]"[[note]]Derived from "mero-mero" -- a Japanese onomatopoeia meaning to swoon with love.[[/note]] with him. Miiko also flirts with him while he's wearing a cat-ear headband, but otherwise doesn't express interest in him aside from as a source of food.
* VerbalTic: Nao has "Umu!" which she often uses as a substitute for "Yes."
* VitriolicBestBuds: Nao and Miyabi constantly bicker and fight over Shinta, but are good friends.
* WhereAreTheyNowEpilogue: The final chapter is narrated by Miiko, who [[spoiler:has become the leader of the cats after Mikadzuki retires and becomes Wakaba's pet. Miyabi leaves the town and becomes Shinta's grandfather's pet, while Shinta dates both of the Nao sisters]].
* {{Youkai}}:
** Inaho, a ''[[AsianFoxSpirit kitsune]]'' and {{Miko}} to Inari, shows up late in the manga.
** Shinta theorizes the transforming cats are ''{{bakeneko|AndNekomata}}'' based on their ability to shapeshift and Miyabi being far [[OlderThanTheyLook older than she looks]].
* {{Yandere}}: Wakaba is initially under the impression that Nao is one for Shinta, and to her credit Nao ''does'' make some menacing remarks.
* YoungerThanTheyLook: Nao is approximately 10 in human years ([[OlderThanTheyLook which roughly translates to 56 in cat years]]), but her human form has the appearance of a 14-year-old girl. Mikadzuki looks to be in his 20s in his human form, but is roughly the same age as Nao.

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