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あいうえお

秋葉・アキバ (AKIBA) = 秋葉原 (Akihabara).
アラサー (ARASA) = Around thirty years old.
アラフォー (ARAFO) = Around forty years old.
アイコラ (AIKORA) = Idol collage; photoshopped/fake images of idols.
アル中 (ARUCHUU) = アルコール中毒 (alcoholism).
アイマス (AIMASU) = IDOL M@STER (video game).
AA (ASUKII ARTO) = ASCII art; picture made using text characters.
AV (AE BUI) = Adult video (porn movies).
あけおめ (AKEOME) = Short for あけましておめでとう (happy new year).
足コキ (ASHIKOKI) = Footjob.
アジカン (AJIKAN) = ASIAN KUNG-FU GENERATION (rock band).
アップ・うｐ (APPU) = Upload.
朝シャン (ASASHAN) = Morning shampoo, i.e. washing your hair in the morning.
アナル・アヌス (ANARU, ANUSU) = Anus.
アナニー (ANANII) = Short for アナルオナニー (anal masturbation).
アコギ (AKOGI) = Acoustic guitar.
アクメ (AKUME) = Orgasm.
青姦 (AOKAN) = Outdoor sex.
アソコ (ASOKO) = "Down there (crotch)".
アニヲタ (ANIOTA) = Anime otaku.
アヘ顔 (AHEGAO) = Exaggerated facial expression showing sexual climax.
アニソン (ANISON) = Anime song.
アルバイト (ARUBAITO) = Part time work. From German arbeit - to work.
あほ・アフォ (AHO, AFO) = Idiot.
アホ毛 (AHOGE) = A bit of hair that stands up on character's heads.
アポ (APO) = Appointment.
アンチ (ANCHI) = Anti; someone that doesn't like you (hater).
いく・逝く・イク (IKU) = To cum.
イケメン （IKEMEN) = Good looking/handsome male.
イラマチオ (IRAMACHIO) = Irrumatio (oral sex where male stands while holding onto the head of the giver and moving it back and forth).
痛い (ITAI) = Hurts (not only physically but emotionally).
板 (ITA) = Bulletin board (forum).
痛車 (ITASHA) = Cars with images of anime/manga characters.
うざい・うぜぇ (UZAI, UZEE) = Way to describe something annoying.
ウイイレ (UIIRE) = Winning Eleven (soccer game made by Konami). Also known as Pro Evolution Soccer.
うｐ (UPPU) = To upload.
薄い本 (USUI HON) = A thin book, i.e. a doujishi.
エロい・エロス (EROI, EROSU) = Erotic.
駅弁 (EKIBEN) = Sex position where male stands holding female.
ED [1] (ENDINGU) = Ending theme song of a TV show or movie.
ED [2] (EEDII) = Erectile dysfunction.
エロゲ (EROGE) = エロいゲーム (adult/hentai game).
エアダッチ (EA DACCHI) = Air Dutch; inflatable love doll.
えるたそ (ERUTASO) = Nickname for Eru Chitanda from Hyouka.
エッチ・H (ECCHI) = [1] Pervert; [2] erotic; [3] sexual intercourse.
エロ本 (EROHON) = エロい本 (porn book or magazine).
エフェクター (EFEKUTAA) = Effector - guitar effects unit/pedal.
エネマグラ (ENEMAGURA) = Enemagra, a type of butt plug designed to stimulate the prostate.
援助交際・援交 (ENJO KOUSAI, ENKOU) = "Assisted dating"; when school girls earn money by dating and sleeping with men (prostitution).
落とす (OTOSU) = To download.
大きなお友達 (OOKINA OTOMODACHI) = "Big friends" - usually refers to adult fans of children's anime and TV shows.
オナニー (ONANII) = Masturbation.
オナテク (ONATEKU) = Masturbation technique.
オナる (ONARU) = To masturbate.
オナペット (ONAPET) = The person you often masturbate to.
オナ禁 (ONAKIN) = To quit masturbation - perhaps to build up your semen and then release at once.
オナホ・オナホール (ONAHO、ONAHOORU) = Onahole, a type of masturbatory aid for men (artificial vagina).
おっき (OKKI) = Funny way to say 勃起 (erection).
オカマ (OKAMA) = Men who dress up in woman's clothes, or look like women.
男の娘 (OTOKONOKO) = Boys that dress up in girl's clothing (trap). Note that the kanji for KO　(娘:girl) is different from 男の子 (子:child) which means "boy".
オフ会 (OFUKAI) = Offline meeting; when people who met online meet in person.
終わコン (OWAKON) = Short for 終わったコンテンツ (finished contents). Used to describe something that has lost its demand for. E.g: books or movies that lost its fan-base.
オレオレ詐欺 (OREORE SAGI) = Form of fraud where the criminal rings up an older person posing as the their relative (often son) asking for money to be deposited into their bank account. Also known as 振り込め詐欺.
乙女ロード (OTOME ROODO) = "Girl's Road", area of Tokyo where many BL (Boy's Love - see below) material are sold.
オネショタ (ONE SHOTA) = Anime or mange showing a relationship between an older female (お姉さん) and a young boy (ショタ).
落ちる (OCHIRU) = To crash (a computer).
OP (OOPUNINGU) = Opening theme song of a TV show or movie.
推しメン (OSHIMEN) = 推しているメンバー the member of an idol group you are supporting.
おかず・オカズ (OKAZU) = The erotic item you masturbate to (book, hentai game, movie etc).
オタ・オタク (OTA, OTAKU) = See ヲタク.
OAD (OOEEDII) = Original anime DVD.
乙 (OTSU) = Short for お疲れ様でした, but often used as offensive word to a person who made effort about worthless things.
オメコ (OMEKO) = Vagina (Kansai dialect).
御大 (ONTAI) = Nickname for Mai from Nichijou (anime).

かきくけこ

カオス (KAOSU) = Chaotic.
カウパー (KAUPAA) = Pre-cum/Cowper fluid. From British doctor William Cowper.
かっくいい・かっけー (KAKKUII, KAKKEE) = かっこいい (Looks cool).
神・ネ申 (KAMI) = "God"; way to describe something very impressive. E.g. 神ゲー, 神動画.
かまってちゃん・構ってちゃん (KAMATTE CHAN) = An attention whore. Someone that loves to be attended to or sympathised with.
ｶﾜｲｿｽ (KAWAISOSU) = To feel sorry for him (in a sarcastic way).
カンペ (KANPE) = Cheat sheet.
カツアゲ・喝上げ (KATSUAGE) = To have your money or items taken off you through violence and blackmail.
カリ・かりくび (KARI, KARIKUBI) = Glans of penis (sensitive round end part of penis). Also known as 亀頭 (KITOU).
ガチ (GACHI) = Short for ガチンコ (being serious, for real). E.g. ガチ泣き, ガチホモ.
ガラケー (GARAKE) = ガラパゴス携帯, type of mobile phone that only developed in Japan.
ガチムチ (GACHIMUCHI) = Male whose body is muscular (ガッチリ) but with body fat (ムッチリ).
ガマン汁 (GAMAN JIRU) = Pre-cum/Cowper fluid.
ガリガリ (GARIGARI) = To be very thin in stature.
ガングロ (GANGURO) = Style of girls with dark skin and dyed blonde hair. From 顔（ガン）を黒（グロ）くする.
カナヅチ (KANAZUCHI) = Being unable to swim, like a hammer.
ガンプラ (GANPURA) = Gundam plastic model.
顔シャ・顔射 (GANSHA) = Short for 顔面シャワー (facial cum). Often written as 顔射 (short for 顔面射精) but it's not origin.
ガン見 (GANMI) = To stare at.
キレる (KIRERU) = When you lose reasoning and burst with anger.
貴腐人 (KIFUJIN) = 腐女子 of major category.
キョロ充 (KYORO JYUU) = A person who keeps looking around him/herself for someone they know. Also see リア充.
逆ギレ (GYAKUGIRE) = When the person being told off turns and starts yelling in the opposite direction.
ギシアン (GISHIAN) = Fucking a girl. A compound word of ギシギシ(noize of a creaking bed) and アンアン(moaning of a girl).
基地外・キチガイ・気違い (KICHIGAI) = Lunatic/retard.
ktkr (KITAKORE) = 来たコレ ("Here it is" as in "I've been waiting for it").
金玉・キンタマ・タマタマ (KINTAMA, TAMATAMA) = Testicles.
騎上位 (KIJOUI) = Sex position where female is on top (cow girl).
クリ (KURI) = [1] Mouse click, [2] clitoris.
くぱぁ (KUPAA) = Expression used when opening woman's vagina (very common in hentai manga).
口パク (KUCHIPAKU) = Lip syncing.
ケモナー (KEMONA) = People who are aroused by furries.
クンニ (KUNNI) = Cunnilingus.
クーデレ (KUUDERE) = A form of ツンデレ, girls who seem cold at first but become soft over time. E.g. Rei from Evangelion.
クレカ (KUREKA) = Credit card.
空気 (KUUKI) = If used in the form 空気を読む, refers to the current mood, e.g. Some one might tell you 空気を読め if you do or say something inappropriate for the situation.
KY (KEI WAI) = Short for 空気が読めない (see above).
空気嫁 (KUUKI YOME) = [1] Inflatable love doll, [2] same meaning as 空気を読め above.
kwsk (KUWASIKU) = 詳しく, asking for more information.
ググれ (GUGURE) = "Google it".
グロ (GURO) = Grotesque.
ぐうかわ (GUUKAWA) = Extremely cute. Fromぐうの音も出ない程可愛い.
グラボ (GURABO) = Graphics board (video card) on PC.
グラドル (GURADORU) = Abbreviated from グラビアアイドル; a gravure idol is a pin-up model that is usually wearing something similar to a bikini.
キモヲタ・キモオタ (KIMO OTA) = Short for キモいヲタク, a 'disgusting/ugly otaku'.
京アニ (KYOANI) = Kyoto Animation Studio.
きもい・きめぇ・キモス (KIMOI, KIMEE, KIMOSU) = Short for 気持ち悪い (gross/disgusting).
逆ナン (GYAKUNAN) = For a girl to pick up a guy. Opposite to ナンパ.
賢者タイム (KENJA TAIMU) = Time just after masturbating, when you suddenly feel relaxed (refractory period).
ケバい (KEBAI) = Glitzy/loud makeup.
ゲー (GEE) = Video game.
ゲロ (GERO) = Vomit.
ゲーセン (GEESEN) = Game center (arcade).
コピペ (KOPIPE) = Copy and paste.
コミケ (KOMIKE) = Comiket (Comic Market), a major doujinshi selling event.
コミヲタ (KOMIOTA) = Comic otaku.
ことよろ (KOTOYORO) = Short for 今年もよろしく (I look forward to seeing you again this year). Often used after あけおめ.
コテハン (KOTEHAN) = 固定ハンドルネーム (using the same alias on forums all the time).
コラ (KORA) = Collage - photo-shopped/fake images.
コクる (KOKURU) = To confess. Usually in romantic sense (confess their love for someone). Short for 告白する. Also コクられる (KOKURARERU) if you are on the receiving end.
コネ (KONE) = Connection/ties. e.g. When you get a job through people you know, this is referred to as コネ就職.
婚活 (KONKATSU) = Act of trying to get married.
ゴスロリ (GOSURORI) = Gothic lolita (style of girls like in Rozen Maiden).
コスプレ (COSUPURE) = Costume play (wearing a anime/game character costume).
合コン (GOUKON) = When a group of males and females go to (say) a bar and try to find a partner.
ゴム (GOMU) = Condom.

さしすせそ

サーセン (SAASEN) = Funny way to say "すいません" (sorry).
鯖 (SABA) = Server computer.
サントラ (SANTORA) = Soundtrack.
△ (SANKAKKEI) = "Mr./ms. ～ is cool". Since rough pronunciation of "～さん格好良い" is similar to "三角形". ex.:"本田△" = "Mr. Honda is cool"
サド (SADO) = Sadist.
三次・三次元 (SANJI, SANJIGEN) = World of 3D (real-life).
ザーメン (ZAAMEN) = Semen (from German "samen").
社畜 (SHACHIKU) = 会社 + 家畜, a slave (farm animal) to his own company.
JK (JOSHI KOUSEI) = Female high school student.
JC (JOSHI CHUUGAKUSEI) = Female junior high school student.
JS (JOSHI SHOUGAKUSEI) = Female elementary school student.
写メ (SHAME) = Photos taken on a phone.
就活 (SHUUKATSU) = Short for 就職活動; act of looking for a full time job (usually after university or high school).
素人童貞 (SHIROUTO DOUTEI) = Male who lost his virginity at a brothel - they are thus a virgin with a non-professional.
ショタコン (SHOTAKON) = Attraction to young boys - term comes from the anime 鉄人28号 where the main character was called Shotaro.
シスコン (SHISUKON) = Sister complex - attraction to your own sister.
知ったか (SHITTAKA) = Know-it-all.
シカト (SHIKATO) = To ignore. From シカと十.
JJI (JIJII) = Old man.
しょこたん (SHOKOTAN) = Nickname for Shoko Nakagawa (voice actor/singer).
信者 (SHINJA) = Fanboy/fangirl. E.g. FF信者 (Final Fantasy fanboy), 林檎信者 (Apple fanboy).
シュール (SHUURU) = Surreal (from French surréalisme). Often used to describe something strange or uncommon.
尺八 (SHAKUHACHI) = Japanese end-blown bamboo flute. Often means blowjob.
シックスナイン (SHIKKUSU NAIN) = Sex position where each person stimulates partner with their mouth (sixty-nine).
しね・死ね・市ね・氏ね (SHINE) = Telling someone to die or go away.
しこしこ・シコシコ (SHIKO SHIKO) = Way to describe sound/motion of male masturbation.
しこる・シコる (SHIKORU) = To jerk off (male masturbation).
自家発電 (JIKAHATSUDEN) = Masturbation.
自宅警備員 (JITAKU KEIBIIN) = One whom is a security guard in their own house (also known as a NEET - see section).
情報弱者・情弱 (JOUHOU JAKUSHA, JOUJAKU) = People with are not well informed because they are unable to use technology.
情報強者・情強 (JOUHOU KYOUJA, JOUKYOU) = Opposite to the above. Someone who is well informed.
すっぴん (SUPPIN) = Wearing no make-up.
スレ (SURE) = Thread (on forum).
スレタイ (SURETAI) = Thread title (topic name).
ストラト (SUTORATO) = Strat (Stratocaster) electric guitar.
ストパン (STOPAN) = Strike Witches (anime/manga). From ストライク and パンツ.
スイーツ（笑） (SUIITSU KAKKO WARAI) = Girls who easily follow trends and are generally dumb. Term comes from the fact that they call deserts 'sweets'.
スルー (SURUU) = To ignore.
すっぽんぽん (SUPPONPON) = To be completely naked.
ステマ (SUTEMA) = Stealth marketing.
スタバ (SUTABA) = Starbucks.
スマホ (SUMAHO) = Smartphone.
センズリ・千擦り (SENZURI) = Male masturbation.
ステハン (SUTEHAN) = 使い捨てハンドルネーム (using a different alias on forums all the time).
スカトロ (SUKATORO) = Scatology/scat - aroused by urine and feces.
ストパー (SUTOPAA) = Short for ストレートパーマ. Straight perm.
スケボー (SUKEBOO) = Skateboard.
せどり (SEDORI) = Buying things cheap then selling online for profit.
前立腺 (ZENRITSUSEN) = Short for 前立腺オナニー, masturbating by stimulating the prostate.
セフレ (SEFURE) = Sex friend (a friend you have just to have sex with).
セルフフェラ (SERUFU FERA) = Giving yourself a blowjob (autofellatio).
正上位 (SEIJYOUI) = Sex position with male on top (missionary).
セクハラ (SEKUHARA) = Sexual harassment.
セクース・セクロス (SEKUUSU, SEKUROSU) = Funny way to say sexual intercourse.
聖地巡礼 (SEICHI JUNREI) = "Pilgrimage", when a manga/anime fan visits places of interest, such as Washimiya Shrine, which was the model for the shrine that Kagami/Tsukasa's parents ran in Lucky Star.
絶対地域 (ZETTAI CHIIKI) = Area between top of socks and bottom of skirt of girls.
ソース (SOOSU) = Source (of information).
ソーロー・早漏 (SOUROU) = Condition which causes men to ejaculate prematurely.
即尺 (SOKUJAKU) = Blowjob before/without man take a shower (in sexual service).
創価・ソウカ (SOUKA) = Souka Gakkai - Japanese Buddhist cult.
草食男子 (SOUSHOKU DANSHI) = Young men who have little interest in sex and relationships.
ソープ (SOOPU) = Brothel.

たちつてと

立ちション (TACHISHON) = To pee outside standing up.
タクティカルパイスラッシュ (TAKUTIKARU PAI SURASSHU) = パイスラッシュ caused by some kind of tactical gear like a sling of a firearm.
～たん (-TAN) = Funny way of saying ～ちゃん:　あいたん instead of あいちゃん.
～たそ (-TASO) = Similar to the above. Also see えるたそ.
タンマ (TANMA) = Time out.
誰得 (DARETOKU) = Short for 誰が得をする? (who appreciate it?), means "seems no one appreciate it." Also use 俺得 (ORETOKU) if you appreciate it.
叩く (TATAKU) = To flame or insult.
タメ口 (TAMEGUCHI) = To talk informally without using 敬語.
田代砲 (TASHIROHOU) = A type of DDoS script for attacking websites. Named after Masashi Tashiro.
ダサい・ダセー (DASAI, DASEE) = Uncool or out of fashion.
大二病 (DAINIBYOU) = 2nd year university syndrome - symptoms include trying to act intelligent when really you have no idea what you're talking about, following trends, bragging on about yourself etc. Also see 中二病.
ダンディー (DANDII) = When a male is well dressed and/or well mannered (from English dandy).
厨房・廚・中坊 (CHUBOU, CHU) = Newbie/noob (Coming from 中学生坊主 [junior high kid]).
チャリンコ・チャリ (CHARINKO, CHARI) = Bicycle.
チョン (CHON) = Korean person (negative term).
ちんこ・チンコ・チィムポ・チン・ポコチン・チンチン (CHINKO, CHIN, POKOCHIN, CHINCHIN) = Penis.
チェリー・チェリーボーイ (CHERRII, CHERII BOOI) = Male virgin.
チャラ男 (CHARAO) = Flashy/fancy looking male. From ちゃらちゃら and 男.
ちゃんみお (CHANMIO) = Nickname for Mio from Nichijou (anime).
チクる (CHIKURU) = To nark on.
乳袋 (CHICHI BUKURO) = When a girl's breasts show clearly on their clothes.
池沼・知症 (CHISHOU) = Short for 知的障害者. Mentally handicapped person.
中二病 (CHUUNIBYOU) = 2nd grade junior high syndrome - symptoms include: becoming angsty, thinking they know everything, being a total dick on the internet etc.
釣り (TSURI) = Trolling (on forums etc).
天然 (TENNEN) = Short for 天然ボケ (TENNEN BOKE), people who are a little short on common sense or seem a bit dumb (but not seriously). Examples include Miyuki from Lucky Star.
ツンデレ (TSUNDERE) = Girls whom are grumpy at first (ツンツン), but become soft over time (デレデレ). Examples include Kagami from Lucky Star.
ツインテール (TSUIN TEERU) = Twin tail (hairstyle like Kagami from Lucky Star or Azusa from K-On); often associated with ツンデレ.
積む (TSUMU) = To end. E.g. 俺の人生詰んだわ - my life is over. 詰む comes from shogi (Japanese chess), equivalent to "check mate".
手コキ (TEKOKI) = Hand job.
低脂肪乳 (TEI SHIBOU NYUU) = Small breasts. The original meaning is "low-fat milk".
手マン (TEMAN) = To fondle a girl's vagina using your hands.
テレキャス (TEREKYASU) = Telecaster electric guitar.
テンション (TENSHON) = 'Tension' (your energy level)" ~が高い.
天パ (TENPA) = 天然パーマ (naturally frizzy hair).
デパ地下 (DEPACHIKA) = Department store + Chika (underground floor) = Area of department store where food is sold.
電波 (DENPA) = Insanity/insane person. 電波 normally means "radio waves", these people believe they are receiving signals from somewhere. E.g. 電波女
テラ (TERA) = "Very" (same sort of thing as "uber" in leet speak).
デジカメ (DEJIKAME) = Digital camera.
デリヘル (DERIHERU) = デリバリーヘルス, form of prostitution where a woman is sent to a customer for sexual services.
電マ (DENMA) = Short for 電気マッサ－ジ機 (electric massager).
DQN (DOKYUN) = Aggressive, uneducated person (similar to a douchebag in English).
DQNネーム (DOKYUN NEEMU) = The type of unusual names that DQN parents give to their children. For more see here: [dqname.jp] http://dqname.jp/. Also known as キラキラネーム.
どさまわり (DOSA MAWARI) = To go on tour as an entertainer.
ドS (DOESU) = Very sadist.
ドM (DOEMU) = Very masochist.
DT・ドーテー (DOUTEI) = 童貞, male virgin.
どじっ娘・ドジッ娘・ドジッ子 (DOJIKKO) = Girls that makes lots of silly mistakes e.g. Osaka from Azumanga Daioh or Yui from K-On.
泥 (DORO) = Android (operating system).
同人 (DOUJIN) = Literally "same people". An activity done by a group of people who have similar interests.
同人誌 (DOUJINSHI) = A book made by a group of people (see 同人 above) as a hobby and not for commercial purposes.
ドヤ顔 (DOYAGAO) = Facial expression showing confidence. From どうや and 顔.
ドタキャン (DOTAKYAN) = To cancel something at the last minute. Short for 土壇場でキャンセルする.

なにぬねの

なつい (NATSUI) = 懐かしい (describing something you fondly remember from old).
なう (NAU) = "Now" as in doing something now e.g. アキバなう.
ナウい (NAUI) = (Archaic) Something modern (it's "now", e.g. fashion).
ナンパ (NANPA) = To pick up a girl.
ナルシスト (NARUSHISUTO) = Narcissist. Someone that loves him/herself too much.
中の人 (NAKA NO HITO) = "The person inside" - the voice actor of an anime character.
中出し (NAKADASHI) = Internal (vaginal/anal) ejaculation of semen.
萎える(NAERU) = To lose interest in something, opposite to 萌える.
夏コミ (NATSUKOMI) = Major Comiket (Comic Market) event held in summer.
ナニ (NANI) = [1] Penis, [2] masturbation.
生尺 (NAMAJAKU, NAMASHAKU) = Blowjob without condom.
生本番 (NAMAHONBAN) = 本番 without condom.
生ポ・ナマポ (NAMAPO) = Another way to say 生活保護 (welfare aid money).
ニート (NIITO) = NEET (not in employment education or training) unemployed young person.
ニコニコ・ニコ動 (NIKONIKO, NIKODOU) = ニコニコ動画 website (http://nicovideo.jp).
２ちゃんねる・２ｃｈ (NICHANNERU, NICHAN) = 2ch board (http://2ch.net).
二次・虹・二次元 (NIJI, NIJIGEN) = World of 2D (anime, manga etc).
ニーソ (NIISO) = Knee high socks.
にわか (NIWAKA) = Newbie.
ニューハーフ (NYUU HAAFU) = "New Half" - Men who dress up in women's clothes or have had a sex change (transvestite).
抜く (NUKU) = [1] To ejaculate semen; [2] To jerk off.
ネトゲ (NETOGE) = Internet game (usually refers to MMORPGs).
寝取られ・NTR (NETORARE) = When a person you have feelings for gets taken by someone else.
ネカマ (NEKAMA) = Males who pretend to be girls online (internet + オカマ).
ネタバレ (NETABARE) = To give away the ending or twist of a story (spoiler).
ねとらじ (NETORAJI) = Internet radio.
ネトウヨ (NETOUYO) = Short for ネット右翼, people who post right-wing political views on the internet.
猫耳・ネコミミ (NEKOMIMI) = Cat ears or girls wearing cat ears (like Azusa from K-On).
ノーコン (NOOKON) = No control or something that is inaccurate.
ノンケ (NONKE) = Non-gay; straight person.

はひふへほ

はがない (HAGANAI) = Short for 僕は友達が少ない (anime/light novel).
腹パン (HARAPAN) = Short for 腹パンチ - punching someone in the stomach.
パクる (PAKURU) = To copy or steal someone else's idea or item.
パクリ (PAKURI) = An item made by copying someone else's idea (plagiarism).
ハッテン場・発展場 (HATTENBA) = A place where gay men go to meet other men to have sex with.
パイパン (PAIPAN) = Shaved pubic area. From Chinese 白板.
パイオツ (PAIOTSU) = Breasts (altered form of オッパイ).
パチスロ (PACHISURO) = Pachinko and slots (gambling).
パチプロ (PACHIPURO) = Professional pachinko player.
パチ・パチ物 (PACHI, PACHIMONO) = Fake (counterfeit) product.
パシリ (PASHIRI) = A person you send to do your errands.
バカ・ヴァカ (BAKA, VAKA) = Fool.
バツイチ・バツ一 (BATSUICHI) = Person who has been divorced once. Can also be バツ二　バツ三 etc.
パンチラ (PANCHIRA) = To get a peek of underpants.
バンプ (BANPU) = BUMP OF CHICKEN (rock band).
バロス (BAROSU) = "ROFL".
ハロワ (HAROWA) = Hello Work (place for people to find jobs).
バスドラ (BASUDORA) = Bass drum.
バックレる (BAKKURERU) = [1] To pretend to not know. [2] To run away or to skip (classes etc).
バイブ (BAIBU) = Vibrator.
BBA (BABAA) = Old woman.
バック (BAKKU) = Sex position where male is penetrating from behind (doggy style).
パワステ (PAWASUTE)　＝ Power steering (in cars).
π/・パイスラッシュ (PAI SURASSHU) = Tits which are emphasised by a belt of diagonally across the body.
パワハラ (PAWAHARA) = Power harassment (abuse of authority).
パイズリ (PAIZURI) = Getting your penis rubbed between breasts (titty fuck).
パッツン (PATTSUN) = Hairstyle where the front is cut straight.
ハンドルネーム・ハンドル (HANDORUNEMU, HANDORU) = Handle name. Your name on forums.
ヒッキー (HIKKII) = Short for 引きこもり (person who is socially withdrawn).
ひとりエッチ (HITORI ECCHI) = Masturbation.
ピザ (PIZA) = Fat person (because they like to eat pizza).
ビッチ (BICCHI) = Slut. From English bitch.
ビーチク (BIICHIKU) = Nipples (altered form of 乳首).
ピンポンダッシュ (PINPON DASSYU) = Ding-dong ditch (ring the doorbell and run off).
ヒドス (HIDOSU) = ひどい (harsh or really bad).
ヒンヌー・ひんぬー (HINNUU) = Small breasts. Altered form of 貧乳.
Vipper (BIPPAA) = Members of 2ch board ニュー速VIP.
プリクラ (PURIKURA) = Print Club - Small stickers with your face on it you get at games arcades.
フェラ・フェラチオ (FERA) = Fellatio.
ファビョる・火病る (FABYORU) = To have your face turn red from anger or embarrassment. From Korean 火病.
ブス (BUSU) = Ugly person.
ブサヨ (BUSAYO) = An ugly person with left-wing political views.
ブラコン (BURAKON) = Brother complex - attraction to your own brother.
ブラクラ (BURAKURA) = A webpage designed to crash your web browser.
ぶっちゃけ (BUCHAKE) = To speak frankly.
ブヒる (BUHIRU) = To find something attractive (anime character etc.). Similar to 萌える.
フルボッコ (FURUBOKKO) = To defeat or smash someone. e.g. 敵をフルボッコにする. (Full + ボコボコ).
BL (BEE ERU) = Boy's Love - anime/manga with gay content (mostly read by females).
ふたなり (FUTANARI) = A person with both male and female sexual organs (hermaphrodite).
振る (FURU) = To reject someone (in the romantic sense). e.g. しつこいから振ってやったわ.
ブラック企業 (BURAKKU KIGYOU) = 'Black company' - companies which treat its employees like slaves with no respect for employment laws. Examples include ワタミ and 東芝.
プレステ (PURESUTE) = PlayStation.
腐女子 (FUJOSHI) = Otaku girls who love BL (Boy's Love - see below) material
フラグ (FURAGU) = Flag; in some computer games (especially hentai games) there are points in the story which branches out into 2 or more paths. The requirements to go into the path you want is known as a flag.
冬コミ (FUYUKOMI) = Major Comiket (Comic Market) event held in winter.
フリーター (FRIITAA) = Freeter; short for free arbeiter. Someone who works multiple part time jobs, instead of a full time job.
フェチ (FECHI) = Fetish, e.g. 足フェチ (ASHI FECHI) - foot fetish.
便所飯 (BENJYO MESHI) = To eat lunch in the toilet because you have no one to eat with.
ベロチュー (BEROCHUU) = Tongue kissing.
ホリエモン (HORIEMON) = Nickname of Takafumi Horie, former CEO of LIVEDOOR (after being arrested for fraud).
本番 (HONBAN) = Performance (also means "no drill"). Often used as sexual insertion (AKA "hardcore").
ホモ (HOMO) = Homosexual.
ホコテン (HOKOTEN) = Pedestrian district, short form of 歩行者天国.
ボッタクリ (BOTTAKURI) = To rip off.
ポニテ (PONITE) = Pony tail.
ぼいん・ボイン (BOIN) = Big breasts.
ボクっ娘 (BOKUKKO) = Girls who refer to themselves as 'boku' (like a boy).
ボンボン (BONBON) = A young man from a wealthy family.
ぼっち (BOCCHI) = Loner. From 一人ぼっち.

まみむめも

マザコン (MAZAKON) = Mother complex - difficulty to move away from mum.
マジ・真剣 (MAJI) = Really, seriously.
マゾ (MAZO) = Masochist.
MAD (MADDO) = Movies made by editing other videos and sounds.
マジキチ (MAJIKICHI) = Short for マジでキチガイじみてるからやめろ, "that's seriously insane/fucked up so stop".
マンコ・マン (MANKO, MAN) = Vagina.
豆乳 (MAMECHICHI) = Very small breasts.
マグロ (MAGURO) = People who don't move on their own during sex.
漫研 (MANKEN) = マンガ研究会 (MANGA KENKYUU KAI), a manga club/circle at school.
マンネリ (MANNERI) = Mannerism, or something that is becoming so common that it's close to becoming a mannerism.
ミニスカ (MINISUKA) = Mini skirt.
ミスチル (MISUCHIRU) = Mr.Children (rock band).
ミンス (MINSU) = 民主党; Democratic Party of Japan.
ミクシー (MIKUSHII) = Mixi, social networking site (http://www.mixi.jp).
耳コピ (MIMIKOPI) = Learning to play a song by ear.
胸熱 (MUNEATSU) = Short for 胸が熱くなる (my heart feels hot) from emotion.
ムカつく (MUKATSUKU) = To be angry about something.
メンヘラ (MENHERA) = Person with mental health problems ("Mental health + er").
メタボ (METABO) = Metabolic syndrome.
メル友 (MERUTOMO) = E-mail friend (friend you talk with through e-mail).
眼鏡っ娘 (MEGANEKKO) = Girls who wear glasses (like Miyuki from Lucky Star).
メシウマ (MESHIUMA) = Short for 他人の不幸で今日も飯がうまい meaning you're enjoying someone else's misfortune.
メアド (MEADO) = メールアドレス, email address.
めんどい (MENDOI) = 面倒くさい; bothersome to do something, e.g.: 朝、ひげを剃るのがめんどい。
萌え (MOE) = Finding something attractive (e.g. anime character etc).
萌え豚 (MOE BUTA) = Otaku who spend a lot of money on bishoujo anime items and are thus considered livestock to the companies.
モチツケ (MOCHI TSUKE) = Funny way to say 落ち着け (OCHI TSUKE), "calm down".

やゆよ

ヤンデレ・病ンデレ (YANDERE) = Girls whose affection for someone leads to strange behaviour (violence/obsession etc) examples include Misaki from Welcome to the N.H.K.
ヤリマン (YARIMAN) = Slut. Also: ヤリチン (YARICHIN), male equivalent.
ヤンキー (YANKII) = A young delinquent.
香具師 (YASHI) = "Guy" as in "that guy". Used in place of 奴 to sound humorous.
801・やおい (YAOI)　＝ Doujinshi with gay content. Short for やまなし・おちなし・いみなし.
ゆとり (YUTORI) = Generation of kids who received ゆとり教育 (no Saturday classes); often seen as idiots online.
百合 (YURI) = Anime or manga with lesbian content.
床オナ (YUKAONA) = To masturbate by rubbing your penis to the floor.

らりるれろ

ラブホ (RABUHO) = Love hotel.
乱交 (RANKOU) = Group sex/orgy.
ラノベ・ライトノベル (RANOBE, RAITO NOBERU) = Light novel - novel with anime characters and informal language (like Haruhi).
らめぇ (RAMEE) = Cute way to say だめ ("stop" or "no").
リアル (RIARU) = Real life.
リョナ (RYONA) = To be aroused by bizarre/wierd (guro, rape etc) content. Short for 猟奇でオナニー.
リア充 (RIAJYU) = リアル＋充実 someone who is living a full life (in real life); has a girlfriend, good job, non-otaku etc.
リスカ (RISUKA) = Wrist cutting (self-mutilation).
林檎 (RINGO) = Apple (computer company).
レス (RESU) = Reply (on forums).
レズ (REZU) = Lesbian.
レゲー (REGEE) = Retro game.
レッチリ (RECCHIRI) = Red Hot Chili Peppers (rock band).
ロリコン (RORIKON) = Lolita complex - attraction to young girls.
ROM (ROMU) = Read only member (lurker).

わをん

wktk (WAKUTEKA) = Short for ワクワクテカテカ, expression showing you are looking forward to something.
ワロタ・ワロス (WAROTA, WAROSU) = "LOL"
猥談・Y談 (WAIDAN) = Talking about dirty subjects (sex, scat etc).
割れ厨 (WARECHUU) = People who illegally download software/music/movies.
ｗｗｗ (WARAI) = "lol"
ヲタ・ヲタク (OTA, OTAKU) = Otaku, people who are very interested in a very niche topic (anime, manga, military, trains etc).

_________________

^ iz dis shit 4 real?

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I accessed it from the war log of a long-dead space-faring race. Yeah, it's real.

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sweet

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That long list of text sure looks important, I think I need to read it comple... OH MY GOD! FREAKAZOIDS!!!!!!!

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Was I really this easily distracted? newfag me was lame.

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don't worry... you're still a newfag

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As an intermediate fag I condemn ye slightly newer fags to perma new fag status. Hah, no, none of that shit matters here. We all learn and grow, and this test right here has nothing at all to do with anything we're talking about but that's what Fuck All is all about.

WHAT KIND OF FUCKING FUCKNIPPLE FUCKWAD FUCKHEAD BULLSHIT OF A FUCKING FUCKTARD ARE YOU YOU FUCKING FUCKED UP FUCKHEADED FUCKING SHITFACED DICKHEAD. I SHOULD FUCKING FUCK YOU UP LIKE BEAT THE FUCKING SHIT OUT OF YOU LIKE FUCKING KILL YOUR WORTHLESS FUCKING RETARD0-FUCK DIPSHIT PEICE OF SHIT FUCKING LIFE IN THE MOST GRUESOME FUCKING PAINFUL FUCKED UP SORTS OF FUCKING WAYS YOU FUCKING PEICE OF FUCKSHIT CUNTWAD NIGGER!

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Ooh, insta-japanese lesson...

Any plans on continuing this?

Yes, learn Japanese.

Then English.