Koishi Komeiji's Heart-Throbbing Adventure (古明地こいしのドキドキ大冒険, Komeiji Koishi no DokiDoki Daibōken), commonly shortened to KoiDoki (こいドキ) or KKHTA, is a fan-made Touhou Project horror series by “Sentakubune” (洗濯船)¹⁾ that began on June 28, 2009.

The series is commonly described as dark, edgy, and excessively violent, but with a method to the “madness”. On the other hand, it takes severe liberties with canon, hasn't aged well, and most fans seem like chuunibyou who are too young to understand the message.

The story opens up with its spin on Japanese mythology, where Tsukiyomi becomes separated from her lover in the Giant Impact,⁹⁾ creating the moon.¹⁰⁾ Millions of years pass and we eventually arrive in the Common Era, where Eirin apparently gives birth to Kaguya's clone during The Tale of the Bamboo Cutter, then they return in August.¹¹⁾ The clone's fate is unclear, with many believing Koishi is the clone.

Gensokyo is created in the late 19th century, then Sanae has her tragic backstory in the mid 20th century.¹²⁾ We then return to the Lunarians embarking on a 380,000km trip to invade Earth in 1972,¹³⁾ slowing once they're 400km away¹⁴⁾ in 1982 and incidentally shred Koishi's body.¹⁵⁾ From here, tragedy falls upon the two satoris, now strung into their plan in the early 1980s,¹⁶⁾ and Koishi goes on a rampage.¹⁷⁾

Forty years have passed since the Lunarians brought world peace, reeducating the human race,¹⁸⁾¹⁹⁾ and our three-day story begins. The Lunarians warn humanity about an imminent threat, while Koakuma and Reisen begin experimenting.²⁰⁾²¹⁾ For October 4th, Satori apologizes at 4:00pm (16:00),²²⁾ madness soaked Gensokyo at 4:25pm (16:25), then Flandre shatters the Great Hakurei Barrier at 6:59pm (18:59).²³⁾

After the Lunarians systematically kill off Gensokyo's inhabitants in their Kaiju form, being hailed as saviors, they conclude their plan of reuniting Tsukuyomi with her lover and turning all living beings into third eyes. Seven years have passed since then. Koishi and a heavily weakened Yukari are shown alive and separated, reflecting on the tragedy that befell upon what used to be Gensokyo in southern Germany.

The story doesn't provide us with an exact year for now, but we can infer the year that it roughly takes place in since it does provide us with a vague time range and the number of years that have passed since then. Obviously, this doesn't mean anything and the story can easily tell us in the final part, so this is primarily a fun thought experiment. Moon phases also don't really mean anything since the moon can be moved.²⁴⁾

As the Lunarian ceremony requires world peace, the Lunarians attempted to absolve mankind of its sorrows by trapping these emotions on the dark side of the moon,²⁶⁾ which had an unintended effect of allowing Gensokyo to absorb the “madness” (狂気, kyōki). Eirin creates the “rain of detoxification” as their temporary solution, but ultimately gets dismissed before she could figure out a proper solution for the madness.

Once the time came, the antagonists experiment on a fairy²⁷⁾²⁸⁾ before unleashing madness on Gensokyo, turning its inhabitants violent while inflicting false memories (e.g. Cirno's inability to remember,²⁹⁾³⁰⁾ Tewi believing she smashed Udonge's legs³¹⁾ when that didn't happen,³²⁾³³⁾ etc.). With the subsequent events, we are led to believe that this step of the plan was a Lunarian cover-up of sorts.

• When the series began, the latest fully released Touhou Project work was Touhou Chireiden.
• The point of Sanae's backstory is that it was meant to give an explanation for Sadistic Sanae, which was a popular fan interpretation at the time. However, it quickly fell out of popularity after Sanae's personality became more fleshed out in canon, causing the sequence to age rather poorly and come off as unnecessary filler that does not ward off the “senseless violence” accusations.
  • In general, Suwako and Kanako's roles are a hard sell. Suwako finds a dried-up Sanzu River with Kogasa after Sanae is killed, and Kanako just brings us to Toyohime at the Hakurei Shrine.
• Furthermore, the series came from a time where fans believed the Watatsuki Sisters were unbeatable with their backstory and performance in the Touhou Bougetsushou series. However, recent Touhou Project works have slowly dismantled “power arguments” in the community, especially after Junko was added in Touhou Kanjuden, where she explicitly overthrows the Lunar Capital.
  • There's a common assumption that people who watch Koishi Komeiji's Heart-Throbbing Adventure before interacting with Touhou Bougetsushou are the ones blindly assuming that the Watatsuki Sisters are evil, but this isn't the series' fault and it dismisses the reality that Touhou Bougetsushou initially wasn't well-received in the Japanese community when the series first released.
  • Junko does make an appearance in Koishi Komeiji's Heart-Throbbing Adventure, but she's killed off in the Hong Kong Special Administrative Region of the People's Republic of China.³⁴⁾
    • Of course, the existence of a people's republic implies that socialism still exists and it raises the question: does the Soviet Union, Yugoslavia, and the GDR still exist here?
  • There's also the error of Renko and Merry existing in the present,³⁵⁾ but this is mostly bad timing as Sumireko didn't canonically exist until 10 months after the video was released.
• Koishi with Yukari's body is officially named “Koishi Yakumo” (八雲こいし),³⁶⁾ though a five-year gap might have led some artists to name the fusion “Yukari Komeiji” (古明地ゆかり) instead.
• In Part 13, the eyecatches with Koakuma and Mamizou are a blatant Kaitei Shujin reference.³⁷⁾
• During the grand fight at the Hakurei Shrine, the Dragon God strikes Yorihime's left eye as it attempts to descend³⁸⁾ before it is quickly removed. To reiterate, Yorihime's eye patch covers her left eye.
• Kaguya's advice about a “Closed Eye of Love” (閉じた恋の瞳, Tojita Koi no Hitomi) is a reference to Koishi's title in Touhou Chireiden, which makes it seem like this was always the series' intention.
• Yorihime's attempt at summoning a Norse god, but getting no response,³⁹⁾ implies that the gods have stopped existing, presumably because humans began worshiping the Lunarians instead.

Toggle chart. (Hey, what were those words before the Part 13 incident?)

• Touhou Igyoukyou - Notably inspired.

• Almost Nothing Beats Doing Laundry on a Sunny Day on Niconico Douga - The official playlist.
  • Sentakubune on Pixiv - Mostly artwork.
  • Sentakubune on YouTube - New!
• Koishi Komeiji's Heart-Throbbing Adventure on Niconico Encyclopedia [JA]
• Koishi Komeiji's Heart-Throbbing Adventure on Pixiv Encyclopedia [JA]
• Koikoi's Heart-Throbbing Adventure on Moegirl Encyclopedia [ZH]
• Koishi Komeiji's Heart-Throbbing Adventure on Namu Wiki [KO]

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