Manga / Serial Killer Reincarnated In Another World

Not all reincarnated people are saints...

Serial Killer Reincarnated in Another World (Serial Killer Isekai Ni Oritatsu) is a 2022 isekai-horror manga written and illustrated by Hitotsubu Ichigo.

A nameless Serial Killer finally serves his death penalty for slaughtering thirteen innocent lives but he could not been happier as it means his insatiable urge to kill people can be put to rest at last. Unfortunately for the murderer, their joy is short-lived as The Goddess had specifically chosen them to be reincarnated in another world and do it all over again.

It turns out they are the last saviour in bringing world peace to the new world as the previous twelve reincarnated saviors had gone off the deep end upon defeating the Demon King and became the new evil who abused their god-like powers bestowed by the Goddess herself.

Now with a new body but the same murderous impulses and zero cheats, Shirukyi is on a mission to rid reincarnated people before they cause untold destruction and genocide in their wake much like they once did only on a global scale.

Contains the following tropes:

• 13 Is Unlucky: The Isekai Killer was convicted of murdering thirteen people before his execution and was the thirteenth person reincarnated by the Goddess with the mission to kill the other twelve reincarnators.
• Abusive Parents: The Isekai Killer had one in the form of his older sister and parental figure in their previous life who taught the ropes on how to be a homicidal maniac like her to a clearly horrified, reluctant child. She eventually groomed them into a uncontrollable Serial Killer with a fair share of volatile neurosis and self-loathing which carried over after being reincarnated. It's no wonder why Shirukyi turned up the way they did.
• Ambiguous Gender Identity: Shirukyi was originally an unnamed male serial killer who reincarnated into a female priestess but doesn't identify as either gender since they hated their uncontrollably homicidal former self and uses feminine pronouns for the latter only out of convenience. Instead, they think of themself as The Isekai Killer tasked with purging the world of reincarnators front and center.
• An Arm and a Leg: Milmil uses spatial vortex to restrain Lunatic in place, proclaiming she can't escape lest she loses a limb or two. What she didn't expect was Lunatic doing exactly that, ripping off both her arms and legs through brute force and instantly regenerating new ones to continue fighting.
• Asshole Victim: Each and every one of the twelve reincarnators on Shuruki's hit list deserves to be put there for how they were endangering the entire new world by abusing their cheats with genocide, violence and tyrannical rule in their wake instead of the world peace promised after the Demon Lord's death. Needless to say, the reincarnators' suffering, Villainous Breakdown and graphic death at Shirukyi's hands are none short of cathartic.
• The Chosen Many: Deconstructed. Desperate at the time, The Goddess reincarnated and empowered a total of twelve people from Earth in hopes they will be powerful enough to defeat the Demon Lord and save the world she watches and protects her entire existence. Unfortunately for her and the world, it made the reincarnators think that they are gods themselves who deserved to lord over everyone else just because they are "special" and joined forces to achieve that goal. Shirukyi is the newest addition, bringing the total to thirteen, so they can take down the other twelve but without the corrupting influence of power this time.
• Cruel to Be Kind: The Goddess assigned The Isekai Killer the seemingly impossible mission of whacking off the other twelve powerful reincarnators without a cheat of their own whether they want to or not so the other world can be saved from those summoned. However, both agree this is for the best because while it would be an uphill battle to take down all of them, having cheats or high levels would most definitely and irreversibly corrupt them, especially with their mental state. The Goddess had already learned her lesson twelve times over and is not going to make the same mistake again for the greater good of humanity.
• Death Seeker: Back before his reincarnation, The Isekai Killer wanted to get caught and executed for his heinous crimes due to being unable to stop himself from murdering innocent people but not having the guts to commit suicide.
  Isekai Killer: He was born for murder. He lived for murder. No one could stop him. A monster who never stopped killing. And for that reason...
  Judge: You are hereby sentenced to the death penalty Prisoner 567! Death row!
  Isekai Killer: Thank you... For killing me...
• Decoy Protagonist: The Goddess reincarnates The Isekai Killer into a new body so he can carry out his mission. The next panel shows Ouga who is set up as an absurdly powerful reincarnated person with a dark, homicidal side, making us to believe he is the Isekai Killer. However as he began killing his party members for no rhyme or reason, it turns out one of them, the low-level, cheatless priestess Shirukyi, was revealed to be The Isekai killer and made swift (and brutal) work of Ouga.
• Disc-One Final Boss: Shrukyi's first two targets, Ouga and Yamazaki, are not even close to the most powerful of the reincarnators with the former dying in the same chapter he debuted in and the latter in two alongside his associates remarking Yamazaki didn't pull his weight or contribute to the Demon King boss fight at all. Their following targets would be significantly stronger, both physically and cheat-wise, and a lot more difficult to assassinate.
• Dwindling Party: The reason for the goddess reincarnating Shirukyi is to eliminate the twelve corrupted reincarnators one by one. So far, they're successful in knocking off four of them and condemned one to A Fate Worse Than Death, leaving seven remaining.
• Enfant Terrible: Yui-Chan physically looks the youngest of the reincarnators, talking and behaving like a little six-year-old girl, yet her heart holds the same wickedness as them given she's totally onboard with the genocidal world domination plan. Not to mention her scary necromancy Zombie cheat she had most likely already taken countless lives with.
• Fallen Hero: All reincarnators before Shirukyi eventually become evil beyond redemption in one way or another from their overpowered cheats corrupting them and developing god-like complexes. This reaches its crescendo once the demon king was slain where they now believed to have the right to rule the new world with an iron fist and commit genocide.
• Freudian Excuse: Shirukyi was raised by their homicidal sister who conditioned them into killing innocents and enjoying the high from it like her, making them the unstoppable and insatiable but self-loathing Serial Killer they are in both worlds.
• Ironic Name: Shirukyi translates to "White Snow" but they are nothing like the dainty maiden waiting to be rescued from the Disney fairytale and more like a Grimm Brothers' protagonist who kills the villains in their sleep.
• Karmic Death:
  • Ouga kills people weaker than him For the Evulz and puts pride in his high levels and skills as his Stat-O-Vision had overinflated his ego and made him cocky. This same cockiness had led to severely underestimating Shirukyi, a low-level priestess, who lures him into the dungeon and pits him against an S-ranked monster he barely survived from before they finished him off. Ouga's final moments were futilely begging for mercy at the hands of someone he considers one of his easy pickings and in the very same dungeon he boasts would leave no bodies of his crimes now that he becomes one himself to Shirukyi.
  • Yamazaki was introduced threatening a little girl who he had orphaned by killing her father for not paying back his debt to him. A little orphan girl would become his undoing when Shirukyi had instructed her to shoot him in the back in a manner similar to how he was backstabbed by one of his minions post-reincarnation. What's more, Yamazaki was very, very fond of the Make an Example of Them trope they frequently abused as a Loan Shark so Shirukyi leaves his severed head in the public square to make everyone think twice about going after Frieyu's orphanage.
• Lesser of Two Evils: Shirukyi is a psychopathic serial killer but they are the hero of the story since the twelve reincarnators they were sent to kill are much, much worse, being not only psychopathic serial killers on a genocidal scale with god powers and without any morals Shirukyi still have but are also fated to drive the reincarnated world into devastation and despair under their iron fist more than the Demon King ever will.
• Logical Weakness: The reincarnators tend to overlook the obvious weak spots that come from depending on their cheats too much. This is instrumental for Shurikyi in carrying out their downfalls.
  • Ouga has Status Inspection as his cheat which lets him kill off those weaker than him and counter their attacks by seeing their levels and powers. However, this makes him very cautious about taking any risks, meaning Ouga never challenges himself in battle unless he's absolutely certain he will win, and overconfident in his undeveloped strength and skills against under-leveled people. Thus, he severely underestimates Shurikyi for their novice levels and stats, gets himself lured into the deepest part of the dungeon and is forced to fight an S-class monster he usually stays away from. By the time of defeating the monster, Ouga had already exhausted all his power, magic and body to its limit from lacking experience in dealing with one and became an easy picking for Shurikyi to finish the job.
    • Ouga is also shown summoning his signature broadsword by reaching his right hand into his personal Pocket Dimension and pulling it out. When he tries fighting back Shirukyi, they easily disarmed him by literally stabbing their dagger through his hand and pinning it to the ground, preventing any access to his blade.
  • Yamazaki's Malicious Perception detects anyone with Killing Intent towards him, making him nigh-impossible to sneak attacks while also having the drop on his would-be assailants. This initially gave Shirukyi a hard time until they realise the radar cannot detect people who don't have any malicious intentions or know what they're doing like say a naive orphan instructed to shoot a crossbow blindfolded on their signal as just a simple "prayer". Thus, the little girl unknowingly bypasses the cheat through her innocent nature and nails the Yakuza in the back with a poison-tipped bolt, weakening him enough so Shurikyi can deal the final blow.
  • Silsil and Milmil have the joint cheat of Great Resonance that lets them rapidly release and amplify their vast magic into one another in a never-ending cycle, resulting in limitless magical power that puts any Wave-Motion Gun to shame. Shirukyi, however, simply exploits the fact that the cheat requires both twins and for them to be in close proximity to activate and separates the two by exploding the ground underneath Silsil, trapping her on a lower floor of their tower with them, while Milmil is left to deal with a newly-released Lunatic at the top. Once Lunatic brutally kills Milmil, the cheat is gone forever as her even if Silsil is still alive (Technically).
    • Additionally, their co-dependency on each other and heavy reliance on magic made the sisters Squishy Wizards by nature. While this is somewhat compensated by being immune to all types of Anti-Magic weaker than their magic (Something Sacred had tried taking advantage of but failed), this doesn't apply to their own magic (Silsil gets caught in the tower's magic destruction barriers she set up) or magical beings way more powerful than them (Milmil finds herself completely outmatched by Lunatic as payback for locking her up). Otherwise, Shirukyi likens their solo "battles" as "easy as murdering a weak, defenseless woman".
  • Expanding upon the above incident, Sacred confidently went up against the twins wearing the rare Jewel Of Magical Destruction which not only cannot be destroyed by any means necessary but absorbs 99.9% of all magic attacks which are Milmil and Silsil's main and only form of combat. What he didn't expect was the twins to suddenly bust out Great Resonance and made him realised that (a) the Jewel of Magical Destruction doesn't grant the same invulnerability to its user and (b) 0.1% of infinite magic is still infinite. Predictably, Scared never stood a chance from the start and paid the price by being vaporized into oblivion with the still-intact amulet left for the two's nefarious uses.
  • Razvel possesses a wide range of abilities with Psychic that includes telekinesis, telepathy, clairvoyence and pyrokinesis which would make assassinating her impossible until the anti-faction came up with seemingly fool-proof countermeasures. First, they spread oil around Razvel's living quarters so she wouldn't start fires without setting her entire palace ablaze. Next, the offense team continuously attack her all at once so she wouldn't have time to read their thoughts or predict the future and respond accordingly. Lastly, Frieyu is on support and instantly heals any fatal damage so the fighters can tackle psychic attacks head on without the risk of dying. Unfortunately for them, the faction completely underestimated Razvel and her strength when she proceeded to effortlessly behead everyone but Friyu with her telekinesis. However, the faction's utter defeat led Shirukyi to take over the assassination attempt and give the real rundown of Razvel's abilities.
    • Shirukyi made a careful observation that all the reincarnators they had faced had one power to their cheat so isn't it strange that Razvel is an outlier considering she appears to have several psychic-related powers? That is unless she has been bluffing about the extent of her cheat the entire time using her past life experience as a televangelist and truly only ever had telekinesis as her sole power since it's the one ability she demonstrated without taking her word for it.
    • Furthermore, Shrukyi degrades Razvel's cheat as not even a significant ability as she claims towards the other reincarnators because telekinesis without clairvoyance or telepathy is completely limited to one thing at a time within her vision (Allowing Razvel to be easily blindsided by flashbangs and ambushes from behind or above) and while it has enough force to decapitate someone, it doesn't work on regenerative near-immortals like Lunatic who twist her head back in place to continue her senseless beatdown. This is why The Goddess classified her killing difficulty level as "easy" which Shrukyi just as easily proves when sneaking up behind a distracted Razvel mid-Villainous Breakdown and stabbing her in the neck.
  • Turns out, Shirukyi themself isn't exempted from this despite not having a cheat. The method they used to dispatch the other reincarnators is finding everything there is to know about the targets and exploiting their flaws which is made possible with the comprehensive guidebook the Goddess had given to them before reincarnating comprising of all the information she gathered regarding the reincarnators' background, cheats and past lives. Unfortunately, Shirukyi's relatively smooth-going assassination journey can come to a screeching halt when it regards Sakurako Kuki who is so shrouded in mystery to the extent her cheat is labeled "???" that the Goddess has zero information on her section and issued an apology instead. As such, this makes Sakurako the most dangerous out of the reincarnators and the last on Shirukyi's hit list since they completely lost the element of surprise and their only advantage as well as her cheat being able to take out both them and Lunatic at any time she wants. It was made worse when Sakurako Kuki revealed herself to be Shirukyi's reincarnated older sister who made them the messed-up way they are and taught them everything about the killing business in the first place, making Shirukyi even more reluctant to face her as she knows all their little tricks and her mere presence trigged their Trauma Button from living in constant fear of her during their previous life.
• Meaningful Name:
  • Shirukyi is translated as "Snow White" in Japanese but when spelled backward, it can either mean "murder" or "death". Fitting for a ruthless and bloodthirsty Serial-Killer Killer who poses as an innocent dainty maiden to get closer to her targets.
  • Ouga's name means "eye" which is an obvious reference to his Magic Eye when activating his cheat.
  • Milmil and Silsil come from the respective kanjis Miru ("to watch") and Shiru ("to know") which reflects their Mad Scientist nature as well as how they live in a giant watchtower to figuratively and literally look down upon all lifeforms of the reincarnated world, disregarding them as nothing but guinea pigs to experiment on and torture in their quest for knowledge and power. Their names also rhyme and repeat twice since they are lovers reincarnated as twin sisters in sync with each other in every way possible.
  • Lunatic is self-explanatory enough since she's an eccentric yet homicidal maniac of a demon.
• Morality Pet: Frieyu and her orphanage are this to both Shirukyi and the Demon King's daughter Lunatic. The kids absolutely adore them and the two homicidal women dote on them like crazy in return. Yamazaki threatening the orphans to force Freyu into sexual slavery made Shirukyi's task of killing the lout personal.
• Might Makes Right: The twelve reincarnators think that defeating the greatest evil permits them to rule the isekai world instead, making them no different than the Demon King and Lunatic who share this mindset but to less destructive, genocidal degrees. Later on, Chika reveals she quit The Seven Suns, the guild that accompanied the reincarnators in hunting down the demon king, because she didn't agree with the members' unanimous decision to reap the benefits by allowing the reincarnators to do whatever they what.
• My Name Is ???: When all the cheats are shown, one of them is titled "???" and has yet to be revealed on what it is.
• New Life in Another World Bonus: The Goddess grants those she reincarnates with cheats to aid them in the quest to defeat the Demon King and save the new world from evil. However, this is heavily deconstructed since she was so desperate with whoever she chooses in getting rid of the Demon King that she didn't stop to consider if said reincarnators may let their newfound powers go over their heads and irreversibly corrupt them into unstoppable genocidal monsters with god complexes which end up being the case. Now The Goddess must enlist the help of the protagonist to save the world from the reincarnators themselves as she essentially created twelve more demon lords, each more inhumane and devastatingly powerful than the last, to kill just the one.
  • Shirukyi is a deliberate aversion since the Goddess doesn't want another reincarnator going mad with power, especially when this particular individual is an experienced Serial Killer with severe unresolved mental issues on a world-saving mission to rid of the rest of the corrupted reincarnators. They instead receive a helpful guidebook on the other reincarnators including their cheats, background and previous lives as the most important thing when killing a target is to know everything there is to them. This gives them a fighting chance as they realise the cheats have exploitable flaws within themselves that can lead to the reincarnators' demise.
  • Ouga has Status Inspection which grants him Stat-O-Vision through a Magic Eye to see the levels, stats and special powers of everyone. This lets him kill others for sport with the utmost confidence they are way weaker than him and stay far away from those who aren't.
  • Yamazaki gets Malicious Perception to detect any degree of Killing Intent towards him from a certain recipient and in which direction, making it impossible for sneak attacks and for him to have a built-in radar to hunt down the target.
  • Milmil and Silsil's joint cheat of Great Resonance endlessly transfers and multiplies their already vast magical reserves to one another in a perpetual cycle until it's released as an instant death laser to shame any Wave-Motion Gun.
  • Razvel hits the cheat jackpot as Psychic lets her access a multitude of psychic-related powers including telekinesis, telepathy, pyrokinesis, clairvoyance and foresight to name a few so nobody can't even go near her without their head twisting off in a spinning fountain of blood. However, it turns out Razvel was lying about the extent of her cheat the whole time and has just the telekinesis which is less impressive-sounding and more couterable than the previous cheats Shrukyi dealt with.
  • The remaining reincarnators have cheats we don't know the specifics yet but can speculate based on their titles which include Infinite Leveling (Sato), Stop Watch (Ende Manishsforza), ??? (Sakurako Kuki), Zombie (Yui-Chan), x99999 Lives (The Black Knight), Infinite Words (Unknown) and Ultimate Power (Also unknown) but are implied to be way more powerful than the aforementioned examples above.
• No Name Given:
  • The Isekai Killer's original name was never stated as the judge only called them "Prisoner 567" before their execution and now goes by Shirukyi post-reincarnation. A later Flashback censored out their deadname, meaning they actively don't want to be reminded of their former self.
  • Similarly, the deity who reincarnated Shirukyi is only ever referred to as "Goddess" on her insistence.
  • In terms of cheats, one of the twelve is simply labeled "???".
• One Person, One Power: While The Goddess divinely gifted the reincarnators powers that put them leagues above every other inhabitant in the new world including the Demon King himself, each cheat is only limited to one ability per individual. The exceptions are Shirukyi (Who doesn't have one to begin with) Milmil and Silsil (Who both share the same cheat) and Razvel (Who has a wide subset of powers although it was Double Subverted given she was lying about the extent of her cheat and played it straight).
• Reincarnated as the Opposite Sex: The Goddess deliberately reincarnates the male Isekai Killer into a woman to make it easier for them to get the drop on their reincarnated targets since nobody would expect a petite and feeble woman to assassinate twelve of the most powerful people alive. They don't mind the change however as it further detaches themself from their previous life they rarely want to speak about.
• Serial Killer: What Shirukyi used to be in their past life before becoming a Serial-Killer Killer to hunt what the twelve Reincarnators have become, only on a mass genocidal scale.
• Small Name, Big Ego: Ouga and Yamazaki milk their fame and reputation as one of the twelve all-powerful reincarnators who vanquished the Demon Lord for all its worth but their fellow reincarnators consider them as easily the weakest and second-weakest among their ranks. This does not help that their cheats of seeing stats and detecting Killing Intent only give them an edge over the average experienced adventurer and are not as impressive or broken compared to infinite magic, infinite levels or infinite lives and barely contribute at all when the reincarnators finally confront the Demon King. Still, they believe their comparatively sub-par cheats make them superior to everyone else, only for some novice yet violent priestess to painfully and graphically stab them to death in a dark alleyway as they pathetically begged for mercy.
• Squishy Wizard: Milmil and Silsil may have absolute limitless magic potential, quite literally with their cheat being an infinite magic railgun, but suck hard at physical, non-magic related combat as much as with each other. It doesn't take long for Shrukyi to exploit their Logical Weakness and turn them into two defenseless girls who can't fight for themselves.
• Stat-O-Vision: Ouga's cheat (Status Inspection) in a nutshell where he can see his opponents' levels, stats and unique skills and thus have the unfair advantage of foresight over them. However, all that amounted to was Ouga severely underestimating Shirukyi, fighting an S-ranked monster he usually avoids at all costs and dying horribly for not pushing himself under the delusion his cheat is the true reflection of one's abilities and not just numbers. After his death, no one brought up the concept of levels and stats again since this only applies to Ouga and the Isekai world does not run on RPG mechanics.
• We Hardly Knew Ye: Any party Shirukyi joins to get closer to the reincarnators doesn't last long, no matter how much back-story or build-up to be interesting they may become, due to the insurmountable power gap and lack of preparation to go into battle with essentially The Goddess' patrons. The longest anyone lasted was Sacred the Magic Warrior who only survived two-and-a-half chapters past his introduction before Milmil and Silsil vapourised him.
• Yakuza: Yamazaki runs the Hoga Trading Group which is essentially in all but name with his gang running around the backwater town as predatory loan sharks where Frieyu's orphanage is situated. Yamazaki is no stranger to ultra-violence to get his way and owns multiple strip clubs under the Group's name.

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