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Must not Search

Words that have been recommended to not be search. Also a Japanese wiki rating such things on a danger level of 1 to 7. It is very popular within Japanese internet culture.
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This article contains shocking and offensive content. Read at your own discretion.

Note that these can vary to tame to extreme depending on the person.


The contents of this includes sites, images, videos, ect. of erotic (sexual), gory (R-18G), ghost stories, phobics, surprises, etc.

However, some of them may cause damage to your PC, such as browser crashes caused by PC viruses or web scripts. Therefore, unless you have sufficient immunity, tolerance, and knowledge of personal information leakage and security, you should not search for them out of curiosity (you may need to search for them for academic or research purposes, but even in that case, you need immunity).

If an image, video, or exe (a PC executable file) is hit, the viewer will suffer some kind of damage. Genres include PC damage, grotesque, horror, occult, denpa, insanity, depression, ect. In 2014, TBS aired a one-off TV program which examined search terms and urban legends.


In recent years, videos of people searching for words they shouldn't search for have become popular on video sharing sites. There are many different types of live search videos, so if you're curious about search terms, you can watch along.

Currently, the highest danger level is 7, but at one time there were even danger levels up to 8. The description was "may be life threatening" in bold red letters with a black background. Wiki archives from that time do exist.

Currently, the number of words registered in the Wiki is over 2100.


In this article, only items for which pixiv articles exist or going to (even if they are not included in the Must not Search wiki) are listed.

The contributors, administrators, and authors of this article are not responsible for any unpleasant feelings you may experience as a result of searching.

About Genres

Hall of Fame (殿堂入り)Particularly well known in the Japanese language.
PC Damage (PC被害)Items that cause damage to computers.
Grotesque (グロ, guro for short)Violence and cruel descriptions and expressions, etc.
InsanityAn act that goes against common sense.
SexualItems that fall under the category of adult content.
Surprise (ビックリ)Scary images, malicious prank videos, etc.
Occult/SuspenseMystical or supernatural phenomena. Suspense being there as a sense of danger.
Denpa (電波)Literally means "electromagnetic wave". Something that is totally out of touch with the sensibilities of ordinary people.
Reality (真実)An incident or event that actually happened.
Disease/DeformityUnusual appearance.
Unusual OrganismCreatures or other beings with unusual characteristics or abilities (fictional creatures are also included here).
Joke/Neta (ジョーク・ネタ)Basically, anything that can be laughed off. Neta being a Japanese slang of this.
Mystery (謎)Something whose intent or identity is unclear, mysterious, or whose meaning is not well understood.
Psyche/FlashingContent with heavy flashing, loud colors and music.
Phobic (フォビック)For extreme or irrational fear of or aversion to something.
Horror (ホラー)Descriptions that stir up fear.
Depression (鬱)Tragic content.
FilthThe wiki classifies this as excrement or discharge from the body.


TitleJapaneseGenreDescriptionDanger Level
8teacups.exePsyche/Flashing, Denpa, Surprise, Mystery, PC damageA chaotic, flashing and unintelligible video that is loud at the start.4
Acorn WoodpeckerドングリキツツキUnusual Organism, GrotesqueA bird that can effect people with trypophobia due to them making many holes.2
AcrotomophiliaアクロトモフィリアGrotesque, Disease/DeformityThe fetish of amputees.Not Found
Ai to Yuuki to KashiwamochiDepression, HorrorPuzzle game in the style of Yoshi's Cookie.2
Aiseikai Hospital愛生会病院Denpa, Joke/Neta, Hall of FameSite of a hospital that once existed. Its flashy colors and design became popular on 2ch, and even a flash parody was created.1
Akihabara TapeOccult/Suspense, MysteryA mysterious song on a used cassette tape that someone bought in Akihabara.1
Alzheimer's PainterHorror, Reality,DepressionSelf-portrait painted by a painter affected by Alzheimer's disease.2
AmblypygiUnusual Organism, PhobicSpider, some have been sold as pets.2
Anago-sanJoke/Neta, Hall of FameMore specifically a site that collects voices of the Sazae-san character Anago-san.1
Andrei ChikatiloGrotesque, RealitySerial killer from the former Soviet Union (now Ukraine).2
Endless Summer HolidaysSexual, Depression, GrotesqueA novel in which a girl is kidnapped, confined, and tortured continuously.4
Blue Blanket ButcherOccult/Suspense, Reality, MysteryCreepy murder case.2
Blue Devil蒼い悪魔Grotesque, Joke/NetaSeries of cruel Doraemon videos made in 3D Movie Maker (see here).2
Brazen BullRealityCruel method of execution said to have originated in ancient Greece.2
CandiruUnusual OrganismCatfish from the Amazon. Frankly, more dangerous than a piranha.1
Carro GroceGrotesque, Sexual, Reality, Hall of FameJapanese shock site that compiles erotic and grotesque videos.6
CaterpillarコオイムシUnusual Organism, PhobicThe male has a habit of carrying and protecting its eggs, but that's the gross part.2
Cat SoupねこぢるDenpa, GrotesqueCruel but award-winning anime. This can also mean the manga it was based off of (see Nekojiru).1
Chaos Sudden DeathカオスサドンデスJoke/NetaIn Mugen this happens in the intro after the second round of Dark Donald, a scary/joke image is displayed on all screens and even screams are played at the same time (see here).
Chargeman Ken!チャージマン研!Insanity, Joke/NetaA crazy anime that has a lot of things going for it.1
Cochineal Extractコチニール色素Reality, PhobicPigment made from a certain insect.2
CockroachゴキブリUnusual OrganismHated by mankind.Not Found
Cow's HeadHorrorUrban legend about if you listen to it, you will die within three days.1
CreepypastaクリーピーパスタGrotesque, Horror, Occult/Suspense, SurpriseWestern internet urban legends.3
Darwin Awardsダーウィン賞Joke/Neta, Insanity, RealityA tongue-in-cheek honor for people who died in a "idiotic (unusual) manner".1
Delete ImmediatelyHorror, Occult/SuspenseFake special screen of Japanese text covering the screen with the aforementioned title in Shin Megami Tensei II.2
Demodex FolliculorumReality, Unusual Organism, PhobicMicroscopic mite that can only survive on the skin of humans.2
Depleted Uranium AmmunitionDisease/Deformity, Reality, Hall of FameImages of deformed children born due to radiation hit.3
Doki Doki Literature Club!ドキドキ文芸部!Depression, Surprise, Horror, Grotesque, FilthWhat seems like a dating simulator is really a fourth wall breaking psychological horror game.3
Don't Look for WallySurprise, HorrorA screamer flash game of Where's Wally (Waldo in North America).3
Doraemon the Horror銅鑼衛門Horror, GrotesqueHorror parody of Doraemon by Hideshi Hino.2
Ed Geinエド・ゲインGrotesque, Reality, Insanity, HorrorA murderer who was crafted with dead bodies.4
Ego Ego AtakushiエゴエゴアタクシHall of FameTaiko no Tatsujin songNot Found
Eien to Natta Rusuban: Papa wa KaeranaiDepression18+ game where a girl is subjected to severe humiliation and torture. Used copies are sold for a high price.2
Eight Feet Tall八尺様HorrorJapanese urban legend of a tall woman named Hasshaku-sama who abducts children.1
EihortGrotesqueOne of the Great Old Ones in Cthulhu mythology. Looks like a hydnellum peckii.2
Elfen LiedエルフェンリートGrotesque, DepressionAnime and manga with full of beheadings and dismemberment.3
Elite Saltエリート塩Joke/Neta, Hall of Fame, InsanitySalted daifuku made with sweat. This was done on Downtown no Gaki no Tsukai ya Arahende!! with the members not knowing they ate sweat of a elite member.Not Found
ElsagateエルサゲートSexual, Reality, FilthSocial issue on YouTube and Youube Kids.3
Eudocima TyrannusアケビコノハUnusual Organism, Phobic, HorrorWhile not as scary, it's their larvae that is seen as creepy.1
Faithful Reproduction of a Dream I had Today今日見た夢を忠実に再現Joke/Neta, HorrorMysterious text to speech version of Ievan Polkka with visuals of the 1927 Metropolis Maria's dance scene sped up.1
Female Sage女賢者HorrorCharacter from Dragon Quest 3 but looking up the word in Japanese also shows up a scary face of a woman.3
Futomaki恵方巻きHorror, Hall of Fame, SurpriseMore specifically a Niconico video with a thumbnail of Yui Hirasawa but really is a unrelated horror video.3
GiygasギーグHorror, Psyche/FlashingAntagonist of the MOTHER (Earthbound) series. In MOTHER 2 there's a theory that they have a outline of a baby.2
Gloomy Sunday暗い日曜日Depression, Occult/SuspenseA song said to make people commit suicide when listened.2
GogglegogglePC Damage, Hall of FameFake Google site. Just accessing the site will infect you with a virus. It is now extinct.5
Gomenne GomenneごめんねごめんねGrotesqueVocaloid song about cannibalism.Not Found
Goodbye Dolphin Dreamsイルカの夢でさようならGrotesque, Denpa, Psyche/Flashing, Hall of FameHorror site created by ATOLS as a joke for learning HTML. "Please go ahead after killing me!".3
Hakkouda Snowy March八甲田雪中行軍Grotesque, Depression, RealityLarge-scale distress incident that occurred in Japan in January 1902.3
Happy Tree FriendsGrotesqueVery violent web cartoon by Mondo Media.3
Hong Kong 97香港97Grotesque, Insanity, Hall of FameInfamous unlicensed game by Kowloon Kurosawa. Contains a image of a dead person.3
Hydnellum PeckiiHydnellum_peckiiUnusual Organism, PhobicA mushroom that looks like it's bleeding all over.2
I can't be a bride anymorePhobic, Hall of FameAn eerie painting in red and black depicting a woman with an unusually long neck staring at you by Yuuko Tatsushima.3
I'm a Championアイム・ア・チャンピオンDenpaCreepy commercial form the 1970s (see here).1
IcemanアイスマンGrotesque, Occult/SuspenseKnown as Ötzi the Iceman, seen as a cursed mummy along with Tutankhamun.1
IkigusareDisease/DeformityFictitious deformed idol group.2
ImekenイメケンGrotesque, HorrorStands for image (イメージ) search (the ken (ケン) part coming from kensaku (検索)). In other words, it means traumatizing image search.3
Jellied EelsRealityKnown as the world's most disgusting dish originated in England. Traditional dish eaten in the East End of London.1
John Wayne Gacyジョン・ウェイン・ゲイシーOccult/Suspense, Reality, InsanitySerial killer who enjoyed dressing up as a clown.2
KiviakGrotesque, RealityTraditional wintertime Inuit food from Greenland.3
KotoribakoコトリバコOccult/SuspenseA box that is said to curse a person's entire family to death.2
KunekuneくねくねOccult/Suspense, Hall of FameJapanese internet urban legend called Wriggling Body in English.2
Kure Kure TakoraクレクレタコラInsanity, Joke/NetaTokusatsu kids' show with episode 220 never being rebroadcast. The contents was seen as verbally abusive towards the mentally ill with the character getting the abuse going on a violent rampage.1
Kurutta Kajitsu狂った果実Grotesque, DepressionA romance adventure game known for it's tragic scenes.3
Kuso Miso TechniqueくそみそテクニックSexual, Joke/Neta, Hall of FameGay manga that is very popular within Japanese internet culture.1
KusozuGrotesque9 stages of a woman's decay. Often depicts women such as a Empress to show "No matter how beautiful a woman is they will end up being ugly in the end.".2
La Morena Kumonaiラ・モレーナ・クモナイMysteryNamco original song sung in an unknown language.Not Found
LampreyヤツメウナギUnusual OrganismJawless eel with a with grotesque mouth.2
LeucochloridiumUnusual Organism, PhobicParasites that use snails as hosts.3
Linda³GrotesqueOne of the few games given a 18+ rating on PC Engine.2
Little Baby's Ice CreamHorror, DenpaIce cream company known for the 2012 commercial, "This is a Special Time".1
LiveLeakライブリークGrotesque, Hall of FameA now closed video site that was best known for its shock and gore videos5
LobotomyロボトミーRealityWorld's most dangerous surgery.1
Louis XVIIルイ17世Depression, Insanity, RealityA king of France who lived a tragic life.2
Lover BoyLOVER_BOYRetro game with a nude male protagonist. Recalled and disposed of as subject to regulations.Not Found
LSD: Dream EmulatorLSD(ゲーム)Psyche/Flashing, DenpaFrom the artist Osamu Sato, it's a bizarre psychedelic game that does not call itself a game.2
Madtaro狂気太郎Grotesque, HorrorA site for atrocity-related internet novels.2
Make Me CuteかわいくさせてHorror, Phobic, Surprise, Mystery, Joke/Neta, Hall of FameA scary edited image of a doll that 2channel were made to make it cute. On the English side of the internet it is best known the Ahenobarbus Henocied Facebook controversy.
Marimo-chan Bye ByeGrotesque, DepressionImage of Jinguuji Marimo in Muv-Luv Alternative with a exposed crushed head.4
Matsuyama Doctor HarassmentHorror, Sexual, Grotesque, Phobic, Psyche/Flashing, Denpa, Insane, Hall of FameA harassment movement on Matsuyama Kyowa Hospita of shock sites disguised as review sites about the affiliated doctors.6
Me!Me!Me!ME!ME!ME!Grotesque, SexualErotic, gory music video for Japan Animator Expo.3
Mike the Headless Chicken首なし鶏マイク / 鶏マイクGrotesque, Reality, Hall of FameA chicken who lived for 18 months after his head was cut off.1
Momoiro UsagiももいろうさぎHorror, Denpa, SurpriseAn original song by Healing-P for Kagamine Len.2
MopemopeHorror, Hall of Fame, Phobic, SurpriseControversial music video almost falling into Elsagate territory by being heartwarming at first glance.2
Mortal KombatモータルコンバットGrotesqueA brutal fighting game known for it's gory fatality animations. In a more scarier note this had effected the mental toll of the animators due to the references they used.4
My Neighbor TorotoroHorror, Grotesque, Jokes/Neta, Hall of FameInfamous image of Totoro with corpses in his mouth. Finding the original artist seems fruitful...most likely not as popular to be searched for compare to the Jeff the Killer image.2
Nagoya Host Club 2001Insanity, DepressionA crime where male brothel owner and a female witness was shot.3
NarutaruなるたるGrotesque, Sexual, DepressionKnown as Shadow Star internationally. This work is characterized by many extreme scenes.3
Natsumi Step!なつみSTEP!Horror, Occult/Suspense, Hall of FameHorror web anime made in flash. Takehara Minoru most popular work, even been seen by quite a few people in the west.1
NeedlefishUnusual Organism, GrotesqueA fish that can jump out of the sea and kill people.3
NishikigaoHorror, Jokes/Neta, PhobicGame glitch where a character's face becomes distorted.1
Noroi-chanノロイちゃんHorror, Joke/Neta, SurpriseA character from Shakin! (see here).1
NugumuンヌグムHorror, Surprise, Mystery, Hall of FameA self-proclaimed Virtual Youtuber.2
Ochonan-sanおちょなんさんHorrorSomething from Fuan no Tane.Not Found
Ogiwara CrazyHorror, SurpriseThe ending of Crazy Pierrot is screamer image said to be the game creator Yoshiaki Ogiwara.3
Omoikkiri DON! Broadcast AccidentおもいッきりDON!放送事故HorrorEerie broadcast accident of unknown cause.2
Otomushi o Tsukamaero!音虫をつかまえろ!Joke/Neta HorrorTaiko no Tatsujin song.Not Found
panapp FaceHorror, Joke/NetaAn ice cream that, depending on how you eat it, can create a creepy face.1
PennywiseHorror, Joke/NetaClown character from the movie IT1
Pingu 24th EpisodeHorror, Denpa, Joke/NetaAn episode seen so horrific that it has been banned in some countries.1
Pipa PipaUnusual Organism, PhobicA frog that can trigger people with trypophobia.3
Popee the PerformerポピーザぱフォーマーGrotesque, Joke/NetaCG' kids anime known for it's over the top violence.2
Pony IslandPonyIslandHorror, DenpaWhat starts as a cute game becomes unsettling.2
Red Room赤い部屋Horror, Hall of FameA popular flash animation in Japan.2
RoadkillGrotesque, RealityAnimals killed by car.3
Rosalia Lombardoロザリア・ロンバルドReality, DepressionKnown as the most beautiful mummy in the world.1
Running CirnoPsyche/Flashing, Hall of Fame, Horror, Jokes/Neta, DenpaA video made in MMD of a creepy running animation of Cirno.2
Sada Abe Incident阿部定事件Grotesque, Reality, InsanityJapanese geisha and prostitute who murdered her lover during the Showa Era.2
Saikin Osen細菌汚染Horror, PhobicAnother Vocaloid song with many dark theories.2
Sampoong Department StoreInsanity, RealityDeadliest modern building collapse until the collapse of the World Trade Center.2
Satoru-kunOccult/SuspenseJapanese urban legend of getting any answer from a public phone.1
Saturn Devouring His SonGrotesque, Joke/NetaThere is actually two paintings of this, the more popular one is by Francisco Goya.3
Sawney Beanソニー・ビーンGrotesque, Insanity, RealitySaid to be the head of a cannibal clan.1
Sayonara wo Oshieteさよならを教えてGrotesque, Sexual, DepressionAn erotic and grotesque visual novel by CRAFTWORK with a bad aftertaste.2
SCPGrotesque, Horror, DepressionA site that collects fictional monsters.1
Sennichi Department StoreReality, Occult/SuspenseJapanese department store that went in flames.2
Shojo Tsubaki少女椿Grotesque, SexualMore specifically the manga adaptation Mr. Arashi's Amazing Freak Show and its anime known as Midori in the west.3
Shuji TsugawaOccult/Suspense, Joke/Neta, Horror, Hall of FameA character from one Detective Conan's more depressive episode.1
sm666sm666Horror, Phobic, Hall of FamePiropito, also known as nana825763 on Youtube, is a visual artist known for Username666.3
SpooJoke/Neta, Hall of Fame, HorrorMore specifically Shoko Haida's drawing of the character that became incidentally scary.1
Terrifying Kyou-chanGrotesque, Joke/Neta, InsanityParody of Hitoshi Matsumoto's Obake no Q-taro.3
The Dawn Is Your EnemyHorrorAn Adult Swim bumper to scare away kids.1
This ManThis_ManOccult/Suspense, Joke/Neta, HorrorA marketing stunt featuring a somewhat unnerving picture of a man's face.1
Tiananmen SquareGrotesque, RealityMore on the massacre that took place in Tiananmen Square, Beijing.3
Tomorrow is SundayDepressionWork by Motoo Abiko (Fujiko Fujio Ⓐ). "Tomorrow is Sunday. The day after is also Sunday. Everyday is Sunday..."2
Toro on Holiday Photoトロと休日_写真HorrorA rumored photo of ghost in the game Toro on Holiday.1
TtongsulトンスルRealityKorean alcohol made from human feces. Lacking in info.2
Ukraine 21ウクライナ21Grotesque, Insanity, Depression, Hall of FameTwo infamous murders from Ukraine.6
Ultra-Super-Deluxe-ManウルトラスーパーデラックスマンJoke/Neta, Hall of FameManga by Fujiko F Fujio.1
Utsuo no Koi鬱夫の恋Depression, HorrorRPG based on real experiences. See a let's play here.3
VEAHHorror, Joke/Neta, DenpaMusic video by YouTuber Barbapapa.1
Waita Uziga氏賀Y太Grotesque, SexualBizarre manga artist with his most known work in the west being Mai-chan's Daily Life.3
X-DAY 2000X-DAY2000OtherA song in the 2000 series, a series of Namco original songsNot Found
X MultiplyエックスマルチプライHorror, GrotesqueA retro game that takes place inside a woman's body.2
Yoshie KimuraHorror, Joke/Neta, Hall of FameMain antagonist of Death Forest.3
You Are An IdiotPC DamageA flash virus that would open many windows.4
Yume NikkiゆめにっきPsyche/FlashingGame where you walk around in a dark dream.1

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