“い(１)い(１)よ(４)、来(５)い(１)よ(４)！ (Okay, come on!)”
– Yajuu Senpai

Manatsu no Yo no Inmu (真夏(まなつ)の夜(よ)の淫夢(いんむ), lit. “A Midsummer Night's Lewd Dream”),¹⁾²⁾ often shortened to Inmu (淫夢) or INM, initially referred to Babylon Stage 34, the 2001 gay porn tape that ignited a scandal around a top college baseball draft prospect who would end up undrafted.

Nowadays, it's a catch-all term for a subculture that makes jokes about Japanese gay porn which largely resurfaced in the 2010s as a major foundation block of Niconico Douga's Rei no Are category, reprising its role from Gachimuchi, yet it remains a conflicting subject.

“I was young, playing baseball, and going to college, and my teammates and I needed money.”
– Kazuhito Tadano³⁾

Coat Corporation released Babylon Stage 34 on July 20, 2001 and people slowly suspected that one of the amateur actors was the college baseball pitcher, Kazuhito Tadano.⁴⁾ This tanked his draft value, going undrafted in the 2002 NPB Draft, but he eventually addressed this issue after moving to the United States to join the Cleveland Indians' farm system in 2004, regretting his gay-for-pay mistake.⁵⁾⁶⁾

Afterwards, Tadano eventually returned to join the Hokkaido Nippon-Ham Fighters in 2007, showing up in the 2012 Japan Series where he was thrown out the game for throwing a 'dangerous' pitch.⁷⁾ He'd later retire in 2014,⁸⁾ occasionally appearing as a pitching coach. In 2023, it was last reported that Tadano became a professional scout for the Hokkaido Nippon-Ham Fighters.⁹⁾

It was quite popular to joke about bizarre gay porn, such as Kuso Miso Technique or Hentai Kuso Oyaji, but people generally weren't interested in Inmu back in the 2000s. Most of the blame went to a lack of proper entry points, since the “Karate Club” episode of Babylon Stage 27 wasn't discovered until July 2010, allowing Gachimuchi to take priority since they actually had much more content to work with unlike Inmu.

Then in 2010, Niconico Douga establishes “Rei no Are” and users unearth the “Karate Club” episode, which sparked a huge renaissance of Inmu content with “Yajuu Senpai” as Inmu's new centerpiece. In addition to being a better entry point, people began digging into the massive cache of domestic gay porn, which fed into Inmu's seemingly endless stream of new material to work with.

Babylon Stage 34: A Midnight Summer's Lewd Dream ~the IMP~ (BABYLON STAGE 34 真夏の夜の淫夢 ～the IMP～) is a gay porn tape that contains four episodes, produced by Coat Corporation, that would release on July 20, 2001. Due to Tadano's scandal, the original tape was discontinued by November 22, 2003 while the first episode is notably cut out of reprints and compilations for obvious reasons.

1. Yakuza Threat! The Sports Club's Counterattack (極道脅迫！体育部員たちの逆襲) - [T]
   Three young athletes rear-end a Yakuza member's car, so the Yakuza member confiscates the driver's license and subjects one of them to sadistic gay sex. They eventually turn the tables on him.
2. Model Counterattack! Rapist Recruiter (モデル反撃！犯されるスカウトマン) - [T]
   A part-time employee is picked up by a recruiter for a photo shoot for ¥50,000, but the photographer isn't satisfied and that's when the recruiter reveals that he expected him to be able to suck dick.
3. Voyeurism! And Sadomasochistic Delusions… (盗撮！そしてSM妄想へ･･･) - [T]
   This follows two college roommates and one's been filming the other without permission. They both get drunk and the person who was filming gets a sadomasochistic dream while reviewing the footage.
4. Coma Rape! The Senior Who Became A Beast (昏睡レイプ！野獣と化した先輩) - [T]
   After swimming club, the senior brings a junior home, drugs him with ice tea, and rapes him while he's in a coma. The junior wakes up and they both start revealing their love for each other.

The full tape is about 90 minutes long with the episode timestamps at 1:30, 38:35, 54:04, and 68:02, though most re-uploads eventually get taken down for copyright infringement.

Yajuu Senpai (野獣先輩, lit. “Beastly Senior”), alternatively known as YJSNPI(Yajuu Senpai) or TDKR(Tadokoro), is an amateur porn actor that worked for Coat Corporation from 1999 to 2002. He ended up becoming the centerpiece for his role in the easy-to-understand “Karate Club” episode, which wasn't discovered until 2010. Rumored to be 24 years old for his casting couch interview, he would likely be approaching his late 40s as of 2023.

• The Karate Club's Sex Technique (空手部・性の裏技) - [T]
  Third episode of Babylon Stage 27. The club showers and relaxes in a washitsu when the seniors call the junior out for glancing at them, eventually proceeding to strip him.
• The Fetish Vol. 3 (ザ・フェチ Vol.3 フェチシリーズ初心者編) - [T]
  An amateur porn actor's casting couch interview. The masked interviewer, dubbed Batman by the community, would give him an enema and asks him to defecate.
• Perverted Interviewer SUPER 17 (変態面接官SUPER S17) - [T]
  An interview where he is seen standing up. He would strip down to his underwear, then nude, and the titular interviewer would proceed to rub his genitals, kissing him, and so forth.
• SCOOOP!!! 01: VIRTUAL SEX (SCOOOP!!! 01 VIRTUAL SEX イカせ隊見参!!!) - [▶]
  With a full body virtual reality suit, the man experiences a virtual gay orgy and moans. During the “VIRTUAL SEX” initialization, "Sandstorm" by Darude notably plays.¹⁰⁾
• Coma Rape! The Senior Who Became A Beast (昏睡レイプ！野獣と化した先輩) - [T]
  Fourth episode in Babylon Stage 34, see aforementioned section. Again, he would assume the role of a senior who drugs his junior by spiking the ice tea, giving him the nickname.
• Discovery 6 (DISCOVERY 第六号リアルショック!!青年TYPHOON) - [T]
  The last known interview. For some reason, a scene was cut out from their Discovery 10 compilation. Due to the lack of highlights or lines, this entry is typically forgotten.

Monzetsu Shonen 5 (悶絶少年 其の伍, lit. “Agony Boys 5”) is a gay porn DVD with four episodes that was produced by Acceed and released on April 8, 2010. The full video is almost four hours long. Unlike the aforementioned works, the use of real porn actors allows for more hardcore fetishes, arguably presenting a return to form as the video is partially shock content.

1. Bondage Training (緊縛調教)
   A naive country boy gets roped into bondage. He gets hung and whipped, gets a suspended enema, experiences hot wax torture, etc. Through all the pain, he maintains a shameful erection.
2. Young Boy Kidnapped and Raped (少年拉致強姦)
   A businessman kidnaps a boy wearing a track suit going home from school. The boy trembles as he hits him with a bamboo sword, but the businessman doesn't hold back with his abuse.
3. SM Club (SM倶楽部)
   A masochistic boy comes to receive training for the first time. He's asked to lick someone's shoes, gets whipped, gets his hair cut and receives hot wax torture, then faints from the hardcore training.
4. Perverted Boy Slave Dog Training (変態少年奴隷犬育成)
   A masochistic boy asks to become a good slave dog. The master orders him to eat vegetables from his anus, drink piss, stick a golf ball up his ass, then makes him eat shit.

Coat Corporation is a Japanese gay porn video production company that was founded in 1993, producing works such as Babylon, Power Grip, Out Staff, Perverted Interviewer, The Fetish, etc. The company's own headquarters are located in Shimokitazawa, though their building is best known as the original location for the infamous “Yajuu House” (野獣邸, Yajū-tei)¹¹⁾ which has led to several incidents since 2014.

• Episode 1
  • TDN(Tadano) - The baseball pitcher that played “Miura”, who is told to act like a dog by TNOK before he gets subjected to gay sex. Former centerpiece, a Gachimuchi character was named after him.
  • DB(Daibō) - He plays the junior named “Nakata” in Episode 1, who pulls the “Turning Offense” (一転攻勢, Itten Kōsei) and shoots TNOK in the ass. He briefly served as the centerpiece as well.
  • HTN(Hatano) - The other junior in Episode 1, but mostly serves as a background character in all of this.
  • TNOK(Tanioka) - He plays the Yakuza member that the athletes get in trouble with in Episode 1. He is best known for getting his car rear-ended and getting shot in the ass by DB.
• Episode 2
  • NSOK(Nishioka) - He plays a part-time employee in Episode 2, notably speaks in monotone the entire time.
  • DRVS(Darvish) - The scouter named “Kobayashi” who recruits said employee in Episode 2.
  • SBR(Saburō) - A photographer that ends up on the receiving end in Episode 2. Not much else to say.
• Episode 3
  • GO - He plays a college student in Episode 3 of Babylon Stage 34, but he's actually best known as the charismatic scouter in Episode 1 of Babylon Stage 28 who quickly changes his tone after he manages to trick a gas station employee. The latter has developed the “GO is GOD” meme, though it has been countered with “GO is NOT GOD”, “GO is DUST”,¹²⁾ and “SWK is GOD”.
  • Majime-kun (マジメ君) - The college student, Kono, in Episode 3 who simply gets videotaped.
• Episode 4
  • Yajuu Senpai (野獣先輩) - The “beastly senior” in Episode 4 of Babylon Stage 34. He'd become a new centerpiece after his other works were unearthed.
  • Tōno (遠野) - He plays the junior that Yajuu Senpai invites and drugs in Episode 4, best known for his high-pitched scream dubbed “Tōno's World” (世界のトオノ, Sekai no Toono).¹³⁾
• Miscellaneous
  • Inmu-kun (淫夢くん) - A slow loris who ended up becoming the mascot, since people could not properly identify the squirrel monkey at the beginning of the tape.¹⁴⁾
  • Houseplant (観葉植物くん, Kanyōshokubutsu-kun) - Specifically, the houseplant in TNOK's office.
  • Cicada (セミ兄貴, Semi-aniki) - After all, it was midsummer.

• MUR(Miura) - He plays the bald senior in Karate Club, best known for his “sōdayo” (そうだよ, lit. “that's right”) line, piggybacking on Yajuu Senpai noticing KMR was staring. Depicted as mentally disabled.
• KMR(Kimura) - A junior in Karate Club who gets raped by his seniors, MUR and Yajuu Senpai. Depicted as this serious, tsukkomi character to the two seniors.

• SKGC(Sakaguchi) - The police officer in Babylon Stage 17 who shouts “it's the police!” (警察だ！, keisatsu da!), not to be confused with the “homocop” (ホモコップ) that appears in Babylon Stage 40.
• Pinky (ピンキー) - A generic woman who appears in multiple works. Her unflattering face is usually accompanied with the “Dededon!” (デデドン！) sound of despair.
• SIY(Seiya) - The gas station clerk in Babylon Stage 28 that gets tricked by GO.
• KBS Trio (KBSトリオ) - The trio in Babylon Stage 30 who is known for their infamous “Kane! Boryoku! SEX!” (金！暴力！SEX！, lit. “Money! Violence! SEX!”) line.
• HND△(Honda-san kakke) - The debt collector from Babylon Stage 30 who somewhat resembles Keisuke Honda, therefore his name is a reference to the original “Honda-san kakke” (本田△).
• SNJ(Shinjo) / FFSNJ(Fistfuck Shinjo) - An actor who appears in many works like Babylon Stage 35, though he is best known for his role in SCOOOP!!! 5 where he gets fisted… as the name would imply.
• Generic Passerby Grandpa (一般通過爺, Ippan Tsūkajī) - A random old man with a red shirt that rode his bike in front of the camera during Babylon Stage 42.
• AKNM(Akanuma) - A man who plays American football in Japan Round 6 and Japan Round 9. He is rumored to be the rugby player Genta Akanuma, except nobody knows who he was.
• Miyanaki Michio (宮永通世) - He portrays a monk in Power Grip 104, mostly known for the bell sound that usually accompanies the comment, 33-4.
• NKTIDKSG(Nekutai Dekasugi) (lit. “Necktie Too Big”) - A suit-wearing man with an unusually large necktie, known to be featured in Perverted Interviewer SUPER S 20th and Power Grip 66.

Acceed is a video label for “HINA Co., Ltd.” (有限会社HINA, Yūgengaisha HINA) that emerged in 2006 and features more hardcore fetishes, probably since they use professional gay porn actors.

• Hide (ひで) - He plays a “young boy” in Episode 2 of Monzetsu Shonen 5 who gets kidnapped and raped by the Gyakutai Ojisan. For some reason, everyone pretends to hate him.
  • Hide's OC (ひでのオリキャラ, Hide no Orikyara) - An odd doodle on Hide's pencil case, likely just an indicator of youth. It's a weird lumpy, heart-shaped frog head with lips and pencil limbs.
• Acceed's Three Musketeers (Acceed三銃士, Acceed Sanjūshi)
  1. Gyakutai Ojisan (虐待おじさん, lit. “Abusive Old Man”) - He plays a businessman Episode 2 of Monzetsu Shonen 5 who abducts Hide and hits him with a bamboo sword, but also plays the person who gets his flowerpot smashed in Episode 1 of The Claimer 1 and many other roles.
     • Flowerpot (植木鉢くん, Uekibacki-kun) - This is the flowerpot that gets struck by a volleyball in Episode 1 of The Claimer 1 and sets the tone for the rest of the story.
  2. KBTIT(Kubo Taito) / Takuya-san (タクヤさん) - He plays the trainer in Episode 3 of Monzetsu Shonen 5 with the iconic fishnet shirt and sunglasses, saying “arigato nas!” (ありがとナス！). The name is taken from Bleach mangaka Tite Kubo, which Shōnen Jump isn't happy about.¹⁵⁾¹⁶⁾
  3. Hirano Gengoro (平野源五郎) - The manager in Episode 3 of Monzetsu Shonen 5. Leader of the musketeers. His Twitter account is @acceed_hirano and he actually enjoys Inmu MADs.
• Yuusaku (ゆうさく) - He debut in Prisoner Daisuke. For some reason, he's depicted as a hornet that stings himself,¹⁷⁾ then Nash Music Library's "SC-6804" (NSC-SC-6804) plays at the end.

• Dragon Tanaka (ドラゴン田中) - A gay porn actor that was popular with homosexuals in Osaka, featured in Kurutta Yajuu-tachi from Tequila Video. Rumored to have died of HIV/AIDS. Personally, his best line is his unintentionally native-sounding “WORLD WAR” moan.
• Gaba Hole Daddy (ガバ穴ダディー, Gaba Ana Dadī) - He plays a fat, middle-aged teacher that loves anal play in Gaba Hole Daddy from Thunder Video. Mostly known for his weird moans.
• Genba Kantoku (現場監督, lit. “Field Supervisor”) - He plays the obese masochist who's featured in Kyokon Nikudansen from Samson Video. Best for his unintentional “F.C.O.H.” line.¹⁸⁾
• Kachō (課長, lit. “Section Chief”) - Featured in Kachō Kowareru from Samson Video. He is known for his meowing and moaning.

• In the context of Inmu, “harmful rumors” (風評被害, fūhyō higai), or “reputational damage”, is a term used to describe cases where the community finds something and manages to drag it under their subculture despite it usually having almost zero connection, typically stemming from users attempting to invoke Inmu by pointing out similar expressions, sounds, monotone reading, etc.
• It is possible to visit, or take a pilgrimage to, real-world locations that are now associated with Inmu.
  • Azuma Sushi (あずま寿し) @ 35.6654°N, 139.6706°E (facing west)
    The street where the rear-ending, from Episode 1 of Babylon Stage 34, takes place. The shop has since closed. Since 2015, it was replaced by the “Nakachan-tei” (中ちゃん亭) izakaya.
  • “Yajuu House” (野獣邸, Yajū-tei) @ 35.6657°N, 139.6696°E (facing east)¹⁹⁾
    The north entrance of Coat Corporation's headquarters, where the “こ↑こ↓” scene was shot.²⁰⁾ It has gathered a lot of attention for the August 10th pilgrimages, which are discouraged.²¹⁾
    • As a result, the recent pilgrimages end up at “Kitazawa 3-chōme Park” (北沢三丁目公園)²²⁾²³⁾ or the larger “Kitazawa Park” (世田谷区立北沢公園),²⁴⁾ a short walk east-northeast.
    • Incidentally, the location is 500 meters away from “Shimokitazawa Shelter”, the live music venue that became the basis for “Starry” in Bocchi the Rock, resulting in an unfortunate overlap.
• People have tried to uncover Yajuu Senpai's true identity,²⁵⁾ but it's also a moral dilemma since you're not supposed to know the people in amateur porn in the first place.
  • “Lifetime Online Humiliation” (一生ネットの晒し者, Isshō Netto no Sarashi-mono) is a phrase used to describe Yajuu Senpai and other internet-famous personalities. In response, “Lifetime Online Treasure” (一生ネットの宝物, Isshō Netto no Takaramono) emerged as a positive reinterpretation.
• In the Chinese community, Inmu is rendered as “Zhòngxià Yè zhī Yínmèng” (仲夏夜之淫梦), though “yínmèng” (淫梦, lit. “lewd dream”) may be replaced with “yínmèng” (银梦, lit. “silver dream”) to get past adult wordfilters. Surprisingly, the Inmu culture in China is unusually massive.
• The (首) emoticon, noted for its resemblance to Yajuu Senpai, borrows the kanji for “neck” (首, kubi).
• Yu Darvish is still playing professional baseball in the MLB.

• Gachimuchi
• Rei no Are
  • Cookie☆
• TDN Notation
• Unprecedented Boom

• Manatsu no Yo no Inmu Wiki - Naturally, there's gay porn here, so watch out.
  • Babylon Stage 34 on the Inmu Wiki
  • Yajuu Senpai on the Inmu Wiki
  • Harmful Rumor Damage on the Inmu Wiki - It's a long list.
• Manatsu no Yo no Inmu on the Cookie☆ Explanation Wiki
• Manatsu no Yo no Inmu on Namu Wiki [KO]

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