-->'''Saizo:''' So, you like being a wimpy human?
-->'''Tsukune:''' It's why we come here, right?
-->'''Saizo:''' We should just kill them all… One day we will. When that day comes, will you remember which side you're on?
-->'''Tsukune:''' I'll never forget that.

[[http://www.fanfiction.net/s/6942921/1/He_Who_Fights_Monsters He Who Fights Monsters]] is a [[{{RosarioToVampire}} Rosario+Vampire]] fanfic written by [[http://www.fanfiction.net/u/521293/hawker_748 Hawker 748]]

The story is about what would happen to Tsukune if Moka hadn't crashed into him on the first day of Youkai Academy. While other fanfics generally try and keep the fanservice, comedy and flirting, this one is based around the horror side of the series, asking exactly how far someone would go to survive in an environment where the slightest flaw means weakness, followed shortly thereafter by painful death.

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!!''Fanfic/HeWhoFightsMonsters'' provides examples of:

* AccidentalPervert: Tsukune gropes [[spoiler:Moka]] and [[spoiler:accidentally removes her Rosario]] in chapter eight. [[spoiler:[[WhamEpisode What happens next is a massive shock for eveyone.]]]]
* AerosolFlamethrower: Tsukune's first weapon of choice.
* [[spoiler:AnyoneCanDie]]
* ArmorPiercingQuestion: "Are you sure you're human?"
* AscendedExtra: Keito was a minor villain who only appeared for one episode in the original series. Here her role has increased to main character and [[spoiler:Tsukune's girlfriend]].
* AssholeVictim: While [[spoiler:Tsukune]] has quickly decided that turning to [[spoiler: murdering anyone he fights]] is the best way to solve his problems, with the debatable exception of [[spoiler:Inner Moka]], pretty much everyone deserves what's coming to them.
* AxCrazy: Tsukune becomes this and acknowledges when speaking to [[spoiler:Headmaster.]]
* BadassNormal: Tsukune is a human who kills monsters.
* BattleTrophy: When Tsukune realizes he still has [[spoiler: Moka's Rosario, Keito suggests keeping it and her panties as trophies, claiming he "fucked them both".]]
* BlackAndGreyMorality: Averted, which is a little surprising for such a dark story.
* BreakingSpeech: [[spoiler:Tsukune uses this on on the Headmaster by calling him out on his neglect and the stupidity of his plan for human-monster peace.]]
* BringMyBrownPants: Tsukune accidentally makes a girl piss herself in fear when he almost kills her boyfriend, Hikaru, who is also his old bully.
* BullyingADragon: Tsukune's third fight opens up with what is essentially this. [[spoiler:Though Tsukune is just a normal human, he's made it clear to the school population that he's more than willing to ruthlessly take someone out if he needs to do so. [[WhatAnIdiot The person bullying him is aware of this]].]]
* ChickMagnet: To Tsukune's confusion/dismay he gets more fangirls each time [[spoiler:he kills someone.]]
* CombatPragmatist: Tsukune, oh so much.
* CoveredWithScars: Tsukune realizes this when [[spoiler: Keito]] asks him where each came from.
* CrazyPrepared: Tsukune spends all of his free time making himself ready for a potential life-or-death fight. He has multiple weapon caches in his room.
* CruelAndUnusualDeath: All of them.
* CurbStompBattle: Tsukune's fight with [[spoiler:Harunobu]] is this to the point its almost painful to read.
* CuriosityKilledTheCast: [[spoiler:Saizo]] falls victim to this when he's curious about Tsukune's true form and attacks him to see what it is.
* DarkerAndEdgier: It's [[{{RosarioToVampire}} Rosario+Vampire]] without the fanservice and comedy.
* DatingCatwoman: [[spoiler:Tsukune and Keito's relationship is something like this.]]
* DeathByAdaptation: [[spoiler:Inner Moka. And the last we see of Kurumu is her being taken to Keito's office for "punishment".]]
** [[spoiler:Not ''exactly'' the last thing so far. Tsukune finds Kurumu's hairband and '''bra''' in Keito's Enforcer office. It's all but implied, yet it makes one wonder what ''really'' happened to Kurumu there. ]]
** [[spoiler:Ruby has recently joined them.]]
* DeathByChildbirth: Keito claims she never knew her father, and her mother died soon after giving birth to her. Now consider she's a Jorōgumo. [[spoiler: Anyone who knows the basics of some spider reproduction habits should realize this strongly implies that Keito's mother ate her father, and then Keito devoured her mother soon after hatching. It's no wonder she advises against she and Tsukune having children.]]
* DeconstructionFic: The story is about what Tsukune would be like if he didn't have Moka to protect him and what an ordinary human like him would have to do to survive in a place were everyone is much bigger, stronger and faster than he is.
* DefiantToTheEnd: Tsukune, when he thinks he's about to die. [[spoiler: Specifically, trapped and with his humanity revealed, Tsukune's grimly refuses to beg for his life when given the opportunity and decides to focus on working up enough saliva to spit in Keito's eyes before he dies.]]
* DemotedToExtra: Mizore's only appearance as of chapter 11 was a brief glare at Tsukune after his first murder. In fact, most of the main cast has gotten this treatment. [[spoiler: The ones still alive that is.]]
* DisneyVillainDeath: [[spoiler:Saizo]]
* DistantFinale: The penultimate chapter is only halfway through Tsukune's first year but the final/epilogue implies that Tsukune has [[spoiler: been a teacher at Youkai for several years.]]
* DontTellMama: Tsukune's parents have no idea whatsoever about the things he's getting up to at school.
* TheDreaded: [[spoiler:Tsukune as of chapter 9]]
* DroppedABridgeOnHim: [[spoiler:Ruby and Oyataka]] died when a fire started as a controlled burn to clear the field got out of control.
* ExactWords: Tsukune assures Saizo that he'll "never forget" which side he's on.
* [[spoiler:Eyescream]]: Tsukune does this to [[spoiler:Saizo.]]
* FaceDeathWithDignity: Tsukune's reaction to [[spoiler:Keito learning that he's human.]]
* ForWantOfANail: The whole story is kicked off by Tsukune not getting [[CrashIntoHello hit by Moka on her bike]].
* FromNobodyToNightmare: Tsukune sees this is the path he's on, and freaks out when called on it. [[spoiler:The students and even the Enforcers agree, with Kuyou himself stepping out of Tsukune's way.]]
* GoneHorriblyWrong: The Headmaster wanted a human who would bring peace between humans and monsters. He got [[HeroKiller Tsukune]] instead.
* GroinAttack: Tsukune uses one of these to incapacitate [[spoiler:Harunobu]].
* HappilyMarried: Going by the epilogue, [[spoiler: Tsukune and Keito.]]
* HopeSpot: In Chapter Eight, [[spoiler: Moka]] approaches Tsukune, and is heavily implied to have been working up the courage to say that she likes him. There's even accidental groping, and the story has a moment where it just might turn out alright. [[spoiler: They don't. Oh, God, they don't.]]
* HeWhoFightsMonsters: The whole basis of the plot is Tsukune slowly becoming this trope. Heck, it's ''the name of the story.''
* HeroKiller: Tsukune is an {{Inverted}} version of this trope taken UpToEleven. He's the main protagonist but fits all of the qualifications from being TheDreaded, to [[spoiler:having a high bodycount and killing a main character.]]
* HeroicBSOD: Tsukune has a breakdown after [[spoiler:killing a fellow student for the first time.]]
* [[spoiler:HumansAreWarriors: Tsukune has quickly proven himself to be the most lethal student on campus so far, deadlier than even Inner Moka, ''who he kills''. Tsukune even points out to his fellow students, after having killed two monsters, that humans are experts at fighting dirty.]]
* [[spoiler:IChooseToStay: Tsukune is finally given his transfer papers but immediately rips them up, telling the Headmaster that he's not getting rid of Tsukune that easily and that he no longer belongs amoung humans. He also does it to spite the Headmaster.]]
** [[spoiler: As of the final chapter, Tsukune has become a teacher at Yokai Academy.]]
* ImprobableWeaponUser: Tsukune has used [[AerosolFlamethrower hairspray and a lighter,]] a sharpened butterknife, a fire hose, a chair leg, and several bags of salt to [[spoiler:kill six students, including Inner Moka (not all at the same time; the challengers come one at a time),]] while defending himself.
* ImprovisedWeapon
* ItGetsEasier: Tsukune is initially feels guilty and disgusted when he is forced to kill an opponent. However, by the time he makes his fifth kill, he's barely able to restrain himself from murdering [[spoiler:Yukari]] in cold blood when she gets angry at him for [[spoiler:killing Moka]].
** This gem from chapter 11 highlights it nicely.
--> Tsukune: [[spoiler: "When I have a problem with someone, my first thought isn't how to reason it out, it's about where to find the sharpest object and how much force it would take to get it through a ribcage!"]]
* JumpingOffTheSlipperySlope: Tsukune first only kills when he has no other choice. [[spoiler:In the final chapter he preempts an attack kills the one plotting against him ahead of time]]
* KarmaHoudini: Tsukune sure feels like one. It's more a case of BlueAndOrangeMorality at work, since he ''has'' been protecting himself...
* [[spoiler:KillItWithFire]]: [[spoiler:Tsukune kills his first monster this way. Which leads to him...]]
* [[spoiler:KillItWithWater]]: [[spoiler:...killing his second monster this way.]]
* KirkSummation: The Headmaster ''tries'' to use one on Tsukune. He starts off by explaining that Tsukune has been a "disapointment". Tsukune [[ShutUpKirk tells him to shove it]] and counters with a BreakingSpeech.
* MadeOfIron: Tsukune.
* MeaningfulName: A slightly meta example. Chapter Eight is titled 'Rubicon,' and the phrase 'Crossing the Rubicon' is used to describe passing a point of no return. [[spoiler: Chapter Eight is when Tsukune kills Moka.]]
* MemeticBadass: In-universe example. Over the course of the story, people come to believe Tsukune can and will kill anyone who even slightly annoys him. A student even asks if he really killed two vampires after jumping out a 10th story window.
* MoralDissonance: Tsukune can't believe that others start respecting him more after he kills a fellow student.
* MuggingTheMonster: Bullying the hardened Tsukune was the biggest (and almost last) mistake of Hikaru's (Tsukune's old bully) life.
* MurderIsTheBestSolution: This is Tsukune's default thought process. Everytime he meets someone his first thoughts is how will he most effciently kill him or her if it comes down to a fight. [[spoiler: This is why he chooses to stay at Youkai Academy.]]
* MyGodWhatHaveIDone: In the final chapter, [[spoiler:Kasumi Aono]] breaks down after learning just what Tsukune has gone through, and that [[spoiler:he endured all that hell and has been irrevocably changed because he didn't want to disappoint her]].
* MyGreatestFailure: Tsukune is hellbent on becoming this for the [[spoiler:Headmaster]] just out of spite.
* MythologyGag: While not word for word, Hikaru tells Tsukune to "know his place."
* NiceJobBreakingItHero: The [[spoiler: Headmaster intended Tsukune to show the school that humans and monsters can live together in peace.]] His lack of interference in Tsukune's life and utter lack of protection turned Tsukune into the most feared person in the school, to the point that even ''Enforcers'' are afraid of him, and proved the assumption of "HumansAreBastards" utterly correct.
* NoNonsenseNemesis: Tsukune is once again a heroic version of this trope. All Youkai like to grandstand, gloat about their superiority and power, and follow shonen fighting tropes. Tsukune just kills you without a word.
* NotHyperbole: Tsukune when he tells Hikaru's girlfriend that Keito would kill her for trying to seduce him.
* NotSoDifferent: Keito tells Tsukune that he's like every other student in the school: a monster pretending to be human.
* PreMortemOneLiner: Tsukune doesn't normally do this but he does give a awesome one liner to the first monster he kills
** "Fire needs three things to exist: Heat, oxygen, and a source of fuel. Guess which you are!"
* ProperlyParanoid: Tsukune of course.
* RageAgainstTheMentor: What happens when Tsukune discovers the Headmaster's original plans for him.
* RelationshipUpgrade: [[spoiler:The End of chapter 8 and all of chapter 9 centers around Tsukune and Keito going through this.]]
* SanitySlippage: As of chapter 11, Tsukune has become aware that this is probably happening to him.
* ScarSurvey: [[spoiler:Keito]] asks Tsukune about each of his, leading to his realizing just how many he has.
* ShutUpKirk: [[spoiler:The Headmaster]]'s attempt to call Tsukune out gets turned around into this.
* [[spoiler:SpannerInTheWorks: Tsukune's killing Moka and throwing away her rosary both completely derail Fairy Tale's plans. Not that we see any of this]].
* StrangerInAFamiliarLand: [[spoiler:Tsukune recognizes that his experiences changed him into someone who is too violent to fit into any civilised human school.]]
* SuperWindowJump: Tsukune does this when [[spoiler: Moka]] keeps blocking his attempts to flee via the stairs.
* TeacherStudentRomance: Nekomone seems to have feelings for Tsukune.
* TooDumbToLive: Kanou Nagare (a MonsterOfTheWeek from canon) tries to kill Tsukune even after [[spoiler:Tsukune has killed Moka in her vampire form]]. It ends exactly as [[CruelAndUnusualDeath expected.]]
* TricksterMentor: Deconstructed with the Headmaster. His 'teaching style' created the monster known as Tsukune much to his fear and horror.
* WeCanRuleTogether: [[BigBad Kuyou]] tries to do this to [[spoiler:Tsukune]] by extending multiple offers to him to [[spoiler:join [[EvilMinions The Enforcers]]]].
* WhamEpisode: Tsukune [[spoiler:killing Inner Moka]] in chapter eight came out of nowhere.
* WhyDidItHaveToBeSnakes: A Lamia offers to [[spoiler: be Tsukune's mistress in chapter 10.]]
* {{Yandere}}: Being a Jorōgumo, Keito is naturally fiercely territorial regarding her boyfriend, [[spoiler:Tsukune]].
* VillainousBreakdown: While not evil, just neglectful, it is pretty obvious that the [[spoiler:Headmaster]] is having a massive breakdown behind the scenes.
* YourApprovalFillsMeWithShame: Tsukune feels ashamed and slightly guilty when [[spoiler:Keito]] praises him for his ruthlessness.