[[quoteright:241:http://static.tvtropes.org/pmwiki/pub/images/nanaandkaoru_4912.gif]]
[[caption-width-right:241:Aren't they cute?]]

Nana Chigusa and Kaoru Sugimura have been neighbors and childhood friends for years, but they've started to drift apart in high school. Nana is an ace student and member of the student council, while Kaoru is a BeadyEyedLoser and a slacker. But one day, an... incident occurs to shake up their relationship.

See, Kaoru, as it happens, has a... ''[[UnusualEuphemism thing]]'' for {{UsefulNotes/BDSM}}. One day, his mother, fed up with the weird toys that Kaoru has been wasting his money on, steals all of them to get her son to study instead of spending his evenings jacking off. But since she can't keep them in their apartment (where he'll find them), she asks Nana to keep an eye on them. Nana, wondering what Kaoru has bought, looks through his stuff... and immediately pulls out a [[HellBentForLeather leather one-piece]], which looks suspiciously close to her size. Intrigued, Nana tries on the suit... and locks it in the heat of the moment. Even worse, she doesn't have the key, so it must be in Kaoru's room...

This is the beginning of ''Nana to Kaoru'', an ongoing {{Ecchi}} manga by Ryuta Amazume. It chronicles Nana and Kaoru's adventures in BDSM, from erotic posing and leash-wearing to bondage and blindfold play, and more. It isn't subtitled ''Nana and Kaoru's S&M Diary'' for nothing.

Interestingly, a sequel of sorts called ''Black Label'' chronicles Nana and Kaoru's experience during their summer vacation after graduating. Though it's set 8 months from the comic proper, it's published side by side with it.

Noteworthy for portraying BDSM as something complicated and careful if done willingly, requiring not only trust between the people involved but also preparations and care. Also notable in that it does this without sex ever happening or even being implied (outside of the ''Black Label'' story there's not even any nudity) despite the subject matter it's a relationship/romance manga, not hentai.

An {{O|riginalVideoAnimation}}VA ''and'' a LiveActionAdaptation have been released, the trailer for the live action adaptation is up on the [[http://www.vap.co.jp/tokyo-shishunki/003tr.html website]].

Now with a shiny [[CharacterSheets Character Page]], please [[Characters/NanaToKaoru contribute]].

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!!This series contains examples of:

* AccidentalKiss / SacredFirstKiss: ''[[KissingDiscretionShot Probably]]''. Even Nana and Kaoru aren't sure if it happened or not. It's not actually shown whether or not it actually happened, but according to his following actions in the play, Kaoru seems quite sure that it has; Nana is only shown to touch lips afterwards. But as the end of chapter notes pointed out, [[spoiler: the potential kiss]] wasn't the big movement in their relationship, it was [[spoiler:''Nana realizing she wouldn't have minded kissing Kaoru'']].
* AdaptationalAttractiveness: The live-action adaptation features a much more attractive Kaoru.
* {{Adorkable}}: Kaoru.
* AGlassOfChianti: Part of Kaoru's dream in the first chapter is that he's cradling a glass of red wine.
* AnguishedDeclarationOfLove: The emotions during their breather in chapters 57 to 61 finally get to Kaoru, causing him to face his feelings for Nana head on. [[spoiler:Unfortunately, at the time, she had earplugs and a blindfold on.]]
* AnimalMotifs: Tachi plays mischievous, disobedient kitty cat to Nana's obedient and loyal puppy dog. This gets rather ''explicit'' in chapters 68-70.
* AssShove: One volume is dedicated to Nana and a suppository.
* AuthorAppeal:
** '''BDSM'''
** Girls sticking their tongues out, usually as a sign that they're turned on or being mischievous.
** There is not a panel, not a chapter, but an ''entire volume'' dedicated to asses. More specifically, Nana's ass.
* BarbieDollAnatomy: Genitalia are blanked, except in excerpts from dirty magazines. Largely averted in Arashi.
* BatmanGambit: Tachi knows Nana is both a tsundere and a clingy jealous girl. So to get Nana to join in the breather, she makes a lot of noise like it's already started and he's hurting her. Sure enough...
* BetaCouple: [[spoiler: Black Labels' Shuutarou Sarashina and Mitsuko Tachibana, to the point that they are {{foil}}s to Kaoru and Nana. Both in temperment and in terms of their relationship]]
* BettyAndVeronica: In the mind of the class president's sister in regards to Kaoru, with Nana as Betty and Tachi as Veronica.
* BigBraToFill: The live-action Nana is smaller in both bust and height.
* {{Big Damn Hero|es}}: [[spoiler:Kaoru at the start of chapter 38/YA 16 [[JustInTime saves Tachi]] from a [[CatchAFallingStar nasty fall]]... by using his own body [[ImOkay to cushion the impact]].]]
* BigNo: Nana does this often to Kaouru's BDSM related requests. Just as often, she goes along with them anyway.
* TheBGrade: Nana suffers this. Low-key though.
* {{Blackmail}}: Tachi gets a second "breather" from Kaoru by threatening to tell Nana how much work he puts into their sessions, which would show Nana how deeply Kaoru really feels for her. It's probably for the best that she hasn't threatened to tell anyone else. [[FridgeLogic If you think about it]], Nana's mother is a police chief, while Nana is a class president; Tachi could do some real damage if she felt like spreading rumors.
* BlandNameProduct: The "Moogle" search engine and a "Ricon" camera.
* BlankWhiteEyes: Kaoru has some after [[spoiler: drinking Nana's egg sake]].
* BoundAndGagged: Well, this '''is''' about BDSM after all...
* BrainsAndBondage:
** Nana, though she'd never admit the second part ...[[CovertPervert in public]].
** [[spoiler:Mitsuko, too. She graduated from Tokyo University, arguably the most prestigious school in Asia, and just happens to also run a sex store and is a confirmed, lifelong submissive.]]
* BreastAttack: In ''Black Label'' when Kaoru and Nana go to a nearby river [[spoiler: they find a girl catching fish with her bare hands and give it a go themselves. Nana succeeds only for the fish to escape and land in her cleavage. After failing to get it out herself, the girl ''slaps Nana's breasts together'' which causes the fish to fall through back into the river.]]
* BuxomIsBetter: In chapter one of the first volume Kaoru notes that Nana has very large breasts and calls her "a total knockout"; her breast size is commented upon by ThoseTwoGuys as well.
* CannotSpitItOut:
** Kaoru is afraid a confession would end the [[UnusualEuphemism breathers]]. He's also absolutely terrified of any progress in his and Nana's relationship for the same reason. And he's initially convinced that she's going to leave him behind, so any progress would be useless.
** As much as it is [[CovertPervert blatant]], Nana's fascination with BDSM is something that she has a hard time putting into words. The last time Kaoru pressed the issue, all he got was a LuminescentBlush for the inquiry.
* CaughtTheHeartOnHisSleeve: In a contest of sorts to see who can make the other admit that they want a "breather" first, Nana eventually caves and does this when Kaouru gets up to leave, making a ''very'' elated Kaouru.
* CatSmile: During the [[spoiler: major storm]] in ''Black Label'', Kaoru cooks both her and himself some dinner with whatever was lying around. Nana compliments him while Kaoru tells her, "Stop" and hides his [[CatSmile smiling face]].
* CharacterDevelopment: Yes, '''BDSM''' ''can'' make for some absolutely ''{{a|wLookTheyReallyDoLoveEachOther}}dorable'' character development.
* [[ChekhovsGun Chekhov's Boobs]]: In Volume 9 Chapter 64 [[spoiler: before the 3000m race we see Nana's main opponent staring and thinking to herself "damn her and her huge breasts", at the end of the race it would have been a dead heat except for Nana's larger bust getting to the tape first]]
* ChekhovsSkill: Kaoru's running becomes really important later on when he has to take a DivingSave to protect Tachi, long after everyone's forgotten about it. He's not even winded by the run (although [[NotTheFallThatKillsYou his shoulder is pretty banged up]] from the fall) while his unknown rival, the student council president, is openly exhausted and ''couldn't keep up''. Considering the president is an all around perfect bishonen, and Kaoru is, well, [[{{Gonk}} not]]... [[CharacterDevelopment character]] isn't the [[TookALevelInBadass only]] thing that Kaoru is developing.
* ChekhovsGunman: Mitsuko Tachibana is introduced as just some porn shop manager, whom we later find out has an extensive knowledge of BDSM technique. In Black Label, [[spoiler:she is introduced as Sarashima's sweetheart]].
* ChildhoodFriendRomance: Played with for the Unlucky kind. Kaoru feels this way about Nana in general, but the breathers have given him a chance to connect with her, and the growing attraction each feels for the other could lead to an actual relationship down the road.
* ChivalrousPervert: Kaoru. He tries to be as nice as possible to Nana as he eases her into more and more erotic territory.
** One example involved Kaoru acting as if he left Nana and Tachi, bound up alone in his room for hours. But he carefully watched the whole scene from a window ready to jump into action if anything went wrong. It's worth noting that he was waiting outside in winter weather, which was cold enough to make him sick.
** He also starts working out and running after Nana has a scary run-in with a couple of shoplifters, just so he'll be better able to handle such situations.
* CoversAlwaysLie: While there are plenty that are accurate, a number of covers seem to show Nana as the top.
* CovertPervert: Nana. Having Kaoru draw this side of her out is more or less the driving focus of the story.
* CreatorCameo: Ryuuta Amazume can be heard in the OVA.
* CrosscastRole: As part of Class 2-F's skit in the farewell party, Kaoru is made to wear a swimsuit and wig. Nana helps with his makeup. Alone, in a classroom, with him tied to a chair by the other students to keep him from running away. The role reversal is noted by Kaoru's narration.
** ManInABikini: Well, it's a Playboy bunny-girl swimsuit (including ears), but the effect is the same. Kaoru gives not a single crap.
* CrossPoppingVeins
* CuffsOffRubWrists: Averted, except for Tachi's initial outburst; she complains about her limbs being numb after Kaoru unties her.
* ADateWithRosiePalms: Implied when Kaoru moves the kotatsu into his room... and there's a box of tissues beside it.
* DecompressedComic: To the point where one twenty-page issue started at the beginning of a "breather" and ended after the first spank - out of ten. But it's mostly build-up for the massive amounts of fanservice.
* DidIJustSayThatOutLoud: In Chapter 18 Kaoru brings out a ball gag and then does an {{Infodump}} about the different types of gag used in S&M including images which makes it seem to be directed only to the reader, then we get a BeatPanel of Nana giving him an odd look.
* DidTheyOrDidntThey: Played with -- Nana isn't quite certain if she accidentally kissed Kaoru, but she does realize ''that she wouldn't have minded if she had'', which was a far bigger realization overall.
* DistractedByTheSexy:
** The reason Kaoru can't concentrate on his revision with Nana. [[spoiler:At first, until the nipple clips are introduced.]]
** A variation in Chapter 54, Nana keeps getting distracted by thinking about what Kaoru has in store for their next "Breather". At one point she's apparently been standing in the middle of the girls changing room with a big grin on her face for ''several minutes''. At another, she misses a race starting without her.
* DivingSave: In Chapter 37, Tachi accidently falls down a ledge but lucky for her Kaoru was there to break her fall. And we really do mean ''break'' her fall.
* DraggedIntoDrag: Nana has fun helping Kaoru dress up as a girl in a [[PlayboyBunny bunny]] outfit for a school play.
* DutchAngle: Used as emphasis when something's off or characters are disturbed. One chapter, [[spoiler:after a visit from her deadbeat father]], Nana's panels begin to tilt till the viewpoint's almost at right angles to the rest of the page, matching her current turmoil [[spoiler:at being compared to her mother]].
* DysfunctionJunction: Between Nana, Tachi and Kaoru; We find a host of personal issues that cause them all to be alone and isolated. With Kaoru, it's a massive inferiority complex and lack of self-esteem. With Nana and Tachi, it comes from their motivation to over-achieve which is, in part, a product of their environment.
* EmbarrassingCoverUp: When he had to conceal Nana, who was in full-body bondage gear at the time, from some of her friends and a teacher that walked into his apartment, [[ClosetShuffle Kaoru got her and himself into his bed]] and pretended to be watching a porno. Then, when her grunts were about to give them away, Kaoru made... er... [[ADateWithRosiePalms context-appropriate noises]] to drown out her sounds and gross out their uninvited guests out of his place. It works magnificently and Kaoru thinks nothing of it.
* EroticDream:
** Kaoru starts off the series having a wet dream about Nana as his personal slave.
** A couple of chapters later, we're treated to another scene where Nana is being toyed with by Kaoru. When the scene ends, it's revealed that it was ''Nana'' that had that dream.
* EroticEating: Nana and a chocolate-coated banana at the summer festival in Black Label. [[DistractedByTheSexy Kaoru, and several other guys in the vicinity immediately stop and stare.]]
* EyelidPullTaunt
* FacePalm: Several.
* {{Fanboy}}: Kaoru.
* {{Fanservice}}: Ryuta Amazume has started making a career out of taking various fetishes and putting them into romantic comedies: BDSM this time.
* FanDisservice: Kaoru in a girl's swimsuit. 'nuff said.
* FanNickname: ''Nana to Kaoru: Arashi'', scanlators (and therefore fans) used this to differentiate the main series running in ''Young Animal'' to the newest one running in ''Young Animal Arashi''; in truth the Arashi magazine also referred to the new series as Nana to Kaoru, they didn't feel the need to create a new title till the first collected Volume was published. '''Nana to Kaoru: Black Label''' is the official title of what fans have been calling ''Nana to Kaoru: Arashi'' for quite some time.
* {{Fanservice}}: Nearly all of it's justified by [[MaleGaze schoolboy ogling]] or the 'breathers', out in the open.
* {{Farce}}: "The Crepe Truck On The Hill" arc, where a single misunderstanding leads to Tachi and Kaoru chasing after Nana to protect her modesty.
* ForegoneConclusion:
** [[spoiler:The ''Black Label'' timeskip series has Nana and Kaoru still together and still having breathers (and playing FootsieUnderTheTable). Instant drama kill for any worries 'bout the Student Council President stealing Nana away from him, at least permanently.]]
** However, it also kills the possible [[spoiler:eventual development of Kaoru and Nana admittedly becoming boyfriend and girlfriend in during the 8 months]] the main series must fill to reach the [[spoiler:''Black Label'' timeline]], so it's safe to say the main series must surpass [[spoiler:Black Label's timeline for Nana and Kaoru to truly become a couple.]]
* FriendsWithBenefits:
** Nana and Kaoru have BDSM sessions with Kaoru as the dom and Nana as the sub, but it's a non-sexual versions or at least they tell themselves that they are {{just friends}}.
** Nana and Kaoru actually are FWB with Tachi. Still non-sexual.
* FunbagAirbag: Tachi to the well endowed President's sister.
* FuroScene: Several with Nana and Mitsuko in Black Label.
* GenkiGirl: Mitsuko Tachibana, the porn shop manager. Never has anybody been so "enthusiastic'' about leather, gags, and whips'''♥'''!
** She even takes over Kaoru's position of MrExposition about the finer points of BDSM in ''[=NtK=] Black Label''!
* GenreSavvy: Nana eventually remarks upon the fact that, despite her initial refusals, she ends up doing the things anyway.
* GilliganCut: When Nana discovers the leather one-piece, she thinks about trying it on, but:
-->'''Nana:''' N-No, never. Never! ''Never!!''\\
''cut to Kaoru contemplating his loss''\\
''cut back to Nana wearing the one-piece''
* {{Gonk}}: Both Kaoru and his mother at first, although this is more of a GenericCuteness failure on her part. Both are moving away from this, especially since Kaoru started running and putting some effort into studying.
* GreenEyedMonster: Nana upon seeing Tachi tied up (tighter than she had been).
--> '''Nana''': "God please, somehow... \\
help me to make it look... \\
as though... \\
I'm [[StepfordSmiler still smiling]]."
* GuiltyPleasures: Nana originally just went over to get the key, but the bondage session was a great form of stress relief for her, to the point that it saved her rapidly falling apart school performance. She used that as justification to keep going. Now, she genuinely enjoys and looks forward to her sessions with Kaoru.
** Probably a meta example for some readers.
* HarshWordImpact: The speech bubbles containing Kaoru's lambasting of the class president nearly crowd him out of the panel.
* HelloNurse: Subverted with Nana. Yes, she's gorgeous (in line with the trope), but her imperious manner scares people off.
* HiddenEyes
* HopelessSuitor:
** The class president to Nana.
** Kaoru to Nana... at least in his own mind.
* HotterAndSexier: [[ZigzaggingTrope A very sinusoidal example]]. The series was originally in ''Young Animal Arashi'', a softcore pornography magazine. When it became a runaway success, they moved it to the more mainstream ''Young Animal'' series, and toned the content down. It was still wildly successful, so they have a ''second'' concurrent series -- something that's almost unheard of outside of spinoffs -- ''Nana To Kaoru Black Label'', which takes place after a minor {{timeskip}} and has definitely taken the series back to hotter and sexier territory.
** Kaoru and Tachi, though Kaoru only becomes distressed about it after finding out that [[ViewerGenderConfusion Tachi's a girl.]]
** Averted with Kaoru and Nana using the dental gag - when Kaoru teases Nana about tasting her saliva from his hand, it's another [[MegatonPunch boot to the head]] before he can.
* IconicItem: Nana's hair bow.
* TheInternetIsForPorn: Nana's research. Step 1: enter search term for [BDSM term]. Step 2: receive torrents of porn. Step 3: get entirely the wrong idea about what Kaoru's going to do.
* TheImmodestOrgasm: Chapter 3. She [[BigNo reacted]] badly. [[MegatonPunch Very badly.]]
* ItMakesSenseInContext: Many of the story's more adorable and heartwarming moments aren't so much so out of context.
* JerkassFacade: Kaoru really plays up his sleazy domination role with Nana, although she knows he isn't really like that.
* JerkWithAHeartOfGold: Kaoru again. He is generally unpleasant with everyone, and it's baffling that Nana can even stand his company. He feels the same way.
* KinkySpanking: Not a mere panel, but ''two entire chapters'' are devoted to Nana getting a spanking, plus half of the next chapter just to rub lotion on her sore bottom. And it's clearly an erotic spanking, which is meant to titillate Nana rather than hurt.
* {{Kuudere}}: Kaoru in his "Master" persona.
* LargeHam: When Kaoru and his favorite BDSM author are discussing the books, Kaoru begins ranting and raving about how much they moved him emotionally. The author says, "But after all, they're only porn books." Kaoru: "IS IT WRONG TO BE MOVED BY PORN BOOKS?!"
** Even more funny are his constant facefaults 'bout ''just how moved he is that Kaoru is that moved.'' Kaoru is oblivious, the author is barely keeping himself from screaming out ''[[BigYes yes]]'' and dancing.
* LeaningOnTheFourthWall:
** [[UnknownRival Hiroshi]] angrily thinking to himself that Kaoru's "got a secondary character's face!"
** Sarashina Suutaro is described as being "like a literary master out of some manga". Apparently it's part of his writing process.
* LethalChef: Nana tries her hand at Valentine's Day chocolate in a side story. Key word: ''tries''. The intended recipient actually trembles in his sleep as the trainwreck progresses.
** Her 'extra-healthy' cold remedy makes Kaoru pass out, begin hallucinating, then throw up.
* LoveYouAndEverybody: Tachi says she loves Kaoru to Nana, who, while she wouldn't recognise love if it whacked her upside the head with a rose-covered hammer, still blushes like mad or becomes jealous whenever anyone else trespasses on her feelings towards Kaoru. Tachi backsteps quickly to add "as a friend!"
* LuminescentBlush: This plus sticking her tongue out is Nana's sign that she's intensely turned on.
* MaleGaze: Apart from the specific instances (see Fanservice), Nana almost always takes center stage with a three-quarters or full-body shot during the 'breathers'. Tachi too.
* ManipulativeBastard: Prez's (Yagami Hiroshi) sister Kikuko Yagami
* MarriedToTheJob: Nana's mother. Kaoru's mother is almost always at work, too.
* MarshmallowHell: When Kaoru is hugged by the Porn Shop Manager.
* {{Meganekko}}
* MegatonPunch: Nana's usual method of telling Kaoru he's gone too far with his teasing... unless her arms are tied up; then, it's a Megaton Kick. Kaoru gets smart in a later breather and ties up both her arms and legs.
* MoodWhiplash: Nana is tending to Kaoru who's sick with a bad cold, passed out, and hallucinating due to a home-made cold remedy. [[spoiler:He starts to mumble about Tokyo U and Nana finds a study guide, finally giving Nana a hint about Kaoru's desire to be with her after they graduate]]. She clasps him to her chest to reassure him that she's not going anywhere and he looks into her eyes. It's a wonderful, tender moment... and then Kaoru throws up in her lap.
* MsFanservice: Nana.
* MysteriousAnimalSenses: Hoshino's dog seems to bark whenever it hears the voice of a sexually aroused woman. Kaoru, Doumoto and Hoshino try to use the dog to find out which porn actress fakes her orgasm by watching porn movies all night long. [[spoiler: As soon as the dog hears Nana's voice, it starts to bark like crazy.]]
* NippleAndDimed
* NoCelebritiesWereHarmed: In Chapter 11 when the guys are putting the faces of various girls from their class on the bodies of fetish models, some of the names are similar to real Japanese glamor models.
* NotSoDifferent: On close examination, Nana is almost as isolated as Kaoru.
* NotWhatItLooksLike: When Nana finds Kaoru alone in his room [[spoiler:wearing finger-cuffs and holding a dog on a leash]], and it ''isn't'' a setup for a breather.
* NoSocialSkills: The only excuse Nana has for not figuring out Kaoru's feelings towards her. [[SacrificedBasicSkillForAwesomeTraining Thanks to her studying]], she doesn't consciously recognize attraction outside of blatant horndog-ism.
* ObliviousToLove: Nana hasn't quite picked up on the fact that Kaoru loves her. [[EveryoneCanSeeIt Somehow.]] Nor has she put 2 and 2 together and realized she's in love with ''him''.
** Meanwhile, both their friends pick up on things fairly quickly. Tachi appears to be wavering between wanting to steal Kaoru for herself and wanting to help get them together; Nana's friend in the student council immediately warns her brother about the [[ObliviousToLove deeper meaning]] of her words.
* OhCrap: "Oh crap" faces are frequent. Kaoru's and Nana's are especially amusing.
* OnlySixFaces: Nana shares a lot of features with the other female leads in Amazume's series.
* OutOfGenreExperience: The track day. Excuse me, I ordered a BDSM romance manga; this is highschool sports manga.
* ParentalAbandonment: Kaoru's father is deceased and his mother is a nurse, while [[TheFaceless Nana's mother]] is almost never home.
* ParentsAsPeople: Kaoru's mother is rather well meaning, but being a nurse simply doesn't offer her a lot of time with Kaoru.[[spoiler: And the origins to Nana's ParentalIssues can be found with this trope at work.]]
* PoorCommunicationKills: Nana mistakes Tachi as being her Rival in a love triangle when in reality she's Kaoru's SecretKeeper. What secret? [[spoiler: He's in love with Nana.]] Understandably, it's a bit hard to explain this to Nana... But Tachi also is a bit sweet on Kaoru, too, and is starting to hesitate when doing things that might bring them closer together.
** Specifically, the entire track day is one long string of misunderstandings on the three's parts. Nana keeps seeing Tachi with Kaoru, not realizing Tachi is basically dragging him along to cheer Nana (and herself) on, sees the lunchbox he brought, not realizing it was for Tachi and Nana (mostly Nana), not just Tachi, Kaoru mistakenly thinks that Tachi is the one at his door harassing him for a lunchbox when it was really Nana (and he's too embarrassed to apologize), etc etc.
* PornStash
* PornWithPlot: Only without most of the defining aspects of porn (no explicit nudity, no actual sex)...until the canon-sidestory/TimeSkip chapters of ''Nana To Kaoru: Black Label.''
* PottyEmergency: Tachi during her first "breather," leading to...
* PottyFailure: ...Tachi at the end of her first "breather."
* [[spoiler:RealityEnsues: Turns out that being bound hand and foot in a tight leather outfit without a zipper or precautions for communicating, when you're technically not supposed to be talking, will lead to some trouble.]]
* TheReasonYouSuckSpeech: Kaoru gives a [[SugarWiki/MomentOfAwesome SPECTACULAR]] one to Nana's teacher, club kohai's, and fellow council members, telling them they're pushing too much on Nana, and only thinking about themselves. Cue everyone picking up the slack and falling over themselves to say they're sorry to Nana.
* RedStringOfFate: Mentioned in the end-of-chapter comment, at the end of their [[NotADate totally-not-a-date]] visit to the shrine.
* RidiculouslyCuteCritter: Hiro the puppy from the "Dog" chapters.
* RightBehindMe: Kaoru angrily corrects his friends on the appearance of Nana's breasts...while she's leaning in the doorway.
** [[spoiler:Then Kaoru comes home that very same day to find Nana in his room, [[NotSoDifferent excitedly looking at her picture which she pasted onto the head of a model in his S&M magazine]].]]
* TheRival: Tachi to Nana. Not that Nana cares.
* RunningGag: [[{{Slapstick}} Nana hitting or throwing something at Kaoru]], and Tachi grappling Kaoru against his will.
* SayItWithHearts: Every now and then, especially during particularly touching moments.
* SchoolSwimsuit: Nana often wears one during breathers since they can't wrinkle.
* SecretKeeper:
** Both Nana and Kaoru keep their "breathers" secret from others (indeed, it's part of the thrill). Tachi has also gotten in on it now, and agreed to keep it a secret.
** Inverting it is the student council president and his sister. They're aware of Nana and Kaoru's mutually exclusive secrets -- [[spoiler:namely, that they're in love with each other and oblivious]] -- but instead of keeping the secret, they're trying to exploit the fact that they are unaware.
* SeparatedByTheWall: Nana and Kaoru live in adjacent apartments, and the common wall is between their bedrooms, which they use to signal each other by knocking. They also tend to think about their feelings for each other while staring at it.
* [[SexySantaDress Sexy Santa Bikini]]: Nana's wearing one on the {{fanservice}} art page at the start of Chapter 66. Specifically she's wearing the santa hat and boots and Kaoru's dressed as a Reindeer in the background.
* SheIsNotMyGirlfriend/[[SheIsNotMyGirlfriend He Is Not My Boyfriend]]: variation: Nana and Kaoru each deny being in love with the other when questioned. Apparently [[TwoScenesOneDialogue simultaneously]]. With LoveBubbles behind ''both'' of them.
** As shown in the chapter afterward... [[EveryoneCanSeeIt they are fooling]] '''[[EveryoneCanSeeIt no one]]''' but themselves.
* ShipperOnDeck: Kaoru's mother, at least, is starting to push them together, in the manner of interfering parents everywhere [[spoiler:by asking Nana to take care of him when he's off sick]].
* ShownTheirWork: All about fetish gear and their uses, but yeah...
* ShoutOut: Little Nana bringing home a certificate for winning the [[Manga/DragonBall Tenkaichi Tournament]].
* SmugSnake: The student council president, who openly accosts Kaoru when they're alone, demanding he get on his hands and knees to ''beg'' to see an email when the group gets split up, talking about how he's more deserving of Nana 'cause... well, [[{{Bishonen}} 'cause.]]
** And perhaps because of his SmugSnake personality, his claims get [[ShutUpHannibal epically countered]] by Kaoru, as described in the SugarWiki/MomentOfAwesome described earlier in the article. To quote, after explaining exactly why he and Nana ''aren't'' suited for each other:
---> '''Kaoru''': "One more thing I oughta tell you. Someone like you... Some blockhead like you is not more suited to Nana than I am!! You'd better learn your place. [[SugarWiki/MomentOfAwesome Just give up before Nana dumps you anyway, idiot!!]]
* SpeechImpediment: Kaoru has a stammer when he's nervous (fan translation - unsure whether it's in the original). It gets worse when he's administering the breathers, displaying his nerves and excitement.
* SpitTake
* StupidSexyFlanders: When Nana finishes a race looking more like she's had a 'breather', one of the younger girls feels her heart skip a beat at the sight of it.
* SuspiciouslySpecificDenial:
** Kaoru is somewhat guilty of doing this from time to time. It's part of his [[ICantBelieveAGuyLikeYouWouldNoticeMe issues with Nana and himself.]] This can lead to some curiously funny exchanges among him and those he calls friends...
** Nana can be guilty of this herself, [[CovertPervert but for]] [[BrainsAndBondage different reasons]] and not nearly as much as Kaoru.
* TheTease: Nana, subconsciously [[spoiler:at first. Overtly later on when she's professionally made up and dressed in a kimono, just to go on a shrine visit with Kaoru.]].
** [[spoiler:Specifically, she's wearing a ''furisode'', an advertisement to everyone that she's a [[http://fashion.3yen.com/2007-01-11/types-of-kimonos-furisode/ "Young, single woman available for marriage"]].]]
** Tachi has this habit of always play around with Kaoru in an teasing and[=/=]or [[TheGadfly gadfly]] manner when ever they meet.
** Then in Black Label, [[spoiler: While still at the retreat and before another session, Tachibana is told by Sarashina to tease Kaoru before Kaoru ties her up. Let's just say this much, she doesn't disappoint. Oh and just to note, Sarashina-sensei and Nana are watching while this goes on.]]
* ThoseTwoGuys: Kaoru's friends.
* TimeSkip: A minor one. The "sequel", ''Nana to Kaoru: Black Label'' takes place during summer vacation, where Kaoru and Nana end up being tutored on proper BDSM technique by Kaoru's favorite author. Both are running concurrently, with Black Label having ''much'' more adult content (open nudity, for one).
* TinyGuyHugeGirl: One chapter shows Kaoru has to stand on tiptoe to whisper into her ear.
* UsefulNotes/TokyoUniversity
* {{Tomboy}}: The very athletic and boyish looking Tachi.
* TomboyAndGirlyGirl: Tachi and Nana respectively, although Tachi is more obviously feminine during the breathers.
* TookALevelInBadass: Kaoru's been running every morning ever since Nana was accosted by shoplifters during a breather. By chapter 15, he can sprint around town without even breaking a sweat, whereas the much more athletic (on paper) student council president can barely keep up. Similarly, it's spelled out very clearly that Kaoru is every bit Nana's match intellectually, he just has trouble focusing on studying.
* TriangRelations: Type 5 in the student council.
** Tachi, Kaoru and Nana are in a romantic Type 5 - Kaoru's infatuated with Nana while Tachi's developed a crush on Kaoru. What's preventing a traditional type 4 in Black Label is whether Nana can work out [[WhatIsThisFeeling what her growing affections for Kaoru mean]].
* {{Tsundere}}: Nana, although with a twist -- she's the submissive in an on-again-off-again BDSM relationship with her {{Childhood Friend|Romance}}. Thus, she has a very good reason to be embarrassed about her relationship with him, and motive for denying it when asked. Kaoru, meanwhile, is even more abrasive to Nana than she is to him, with a twist: [[spoiler:he's only worried about her reputation, as he sees himself as being beneath her and dragging her down.]]
** Nana switches to type A tsun when her mother finally comes home (using almost the same words as Kaoru, at that).
* TwiceShy: The only people who don't realize that Nana and Kaoru are in love with each other are Nana and Kaoru themselves. Nana almost confesses to him at the start of the chapter in response to his self-depreciating comments about how she must not like being around him (and part of her CharacterDevelopment is her starting to realize her feelings for him), and he's quite open with himself about being in love with Nana. The student council president and his sister are also quite aware of this, and are plotting to get the president and Nana hooked up before the two figure it out. [[spoiler:Given the ''[=NtK=] Black Label'' timeskip has Nana and Kaoru still together, still having breathers, and off at a BDSM author's house for private tutoring in BDSM techniques, actually making out... [[ForegoneConclusion The president isn't going to win this one.]]]]
* TwoScenesOneDialogue: When Sarashi-sensei begins telling Kaoru how he met Tachibana, it switches to Tachibana in the bath telling Nana how she met Sarashi.
* UglyGuyHotWife: An unmarried example, but no one could be blamed for doing a double take at seeing Kaoru and Nana together. Kaoru's friends even take a jab at their supposed unsuitability for each other.
** The entire plot is basically driven by Kaoru's assumption that Nana could ''never'' see him as boyfriend material, which makes it something of an inversion.
* UnresolvedSexualTension: Considering the things that Kaoru does to Nana, the fact that there ''is'' UST is impressive. They're things like BoundAndGagged or KinkySpanking. This is not without some BelligerentSexualTension and pain.
* UnusualEuphemism: After reading this, you will never again be able to talk about "taking a breather" without giggling.
* UrineTrouble:
** Invoked in chapter 6. Nana has to use the restroom, and Kaoru seems to be finding her a restroom, but they go to a clearing and Kaoru wants her to do it there. She is hesitant to do so, but she does give in.
** In chapter 75, she's is suffering from another one, while in her "Dog Girl" outfit. After much panic, and trying to do it as an actual dog would, she finds a way to relieve herself. Kaoru then helps clean her up.
* VisibleSilence
* VomitIndiscretionShot: The viewer is not spared Kaoru vomiting right on Nana as she comforts him. (Un)Fortunately, Nana covers most of the shot.
* WhenAllYouHaveIsAHammer:
** [[spoiler:Kimono's come undone? Fetch the rope and bind her breasts with bondage ties so it'll fit better.]]
** Need to motivate a member of the track team? [[spoiler:Propose tying Kaoru up to learn how to push people's buttons.]]
* WriteWhoYouKnow: It's implied in Black Label that Sarashina-sensei uses this to come up with the plot of his books.
* WrongGenreSavvy: The poor student council president realizes that Kaoru has a [[{{Gonk}} secondary character's face]], but doesn't realize he's in an {{Ecchi}}, UglyGuyHotWife comedy. He's also absolutely dumbfounded at Kaoru's sad, depressed resignation about Nana being way outside of his league, expecting some form of argument or fight.
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