Inyouchuu Lore Discussion

Thought this would be a good thread to finally put down here. Just sharing lore and trivia! I've run into little tidbits here and there, looking through other sites in the process of trying to archive the knowledge, and I figured why not make a place to discuss your favorite elements.

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BIG CHUNKY SPOILER WARNING.

I don't want to make everyone miserable with mandatory spoiler tags, since a lore thread would end up filled to the brim with them, so consider this your warning that there will be a great many unmarked spoilers from here onwards.

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Based on the JAST Discord chat, it sounds like @NotImportant is one of our biggest canon lore experts, but let's see what details I can throw into our first post here. For some reason, the second game comes to mind a lot at the moment. I threw a few OG lore bits in here, but I believe he's working on a much more in-depth comparison that I'll be excited to check out, so I won't step on that too much at this time.

• In Shoku, when a lovestruck Kikuka boldly asks Yamato to go out with her, he objects on the grounds that she's a little too young for him. Cue her reveal that the twins are, in fact, 414 years old. Given the "cursed for 400 years" plot detail, one can reasonably assume their original demon attack and subsequent curse happened when they were 14.

• Kikuka's hair is shorter than Ouka's because she had been grabbed/restrained by her hair by one of the monsters before being cursed, and cut it off to escape. Evidently, the curse makes her hairstyle immortal as well.

• Curse, or blessing? I believe it was originally stated in the game that the twins were cursed with immortality by Meioki, the second game's demon boss and the self-proclaimed King of Hell. If I'm understanding correctly, he also stole, possessed, and repurposed their own father's body to create his form. With all that being said, though, a more recent game kind of retcons that, instead going with the story that their mother cast a blessing of immortality on them in order to protect them from a demon invasion, then was killed by the demons before she ever had a chance to lift the effects.

• The Black Cat apartment is a wreck, with maintenance problems and paper-thin walls. Based on the few translated lines that I played through when testing the game on my laptop, the rent is super cheap as a result, though the Black Cats are possibly expected to do maintenance and housekeeping as part of their tenancy deal. That said, the bathroom is actually very nice in comparison with the rest of the apartment.

• There's a partial fan translation of the Etsu text, which I made sure to download from asu's Discord server. And literally the first thing that Mama Shiratori says upon meeting Mikoto again after all this time? "Welcome back, Miko-chan. My, my…… Have you got a little fatter while you were away?"

• Ayagami Village, the Shiratori sisters' hometown, is a six-hour train ride from the Black Cat Branch Office. Which absolutely destroys the "Mom lives within driving distance" scenario depicted in my fanfic Demon Hunting Takes Balls of Steel, but at least it fits among my other reasonable liberties taken for the sake of the story... also, there's the fact that Etsu isn't even considered canon.

• Nightmare is not the first demon boss's name, but only what species of demon he is. This is revealed in the original game alongside more Nightmare lore that I'm looking forward to hearing in full sometime. Apparently, hundreds of years ago he was beaten down by a group of exorcists and sealed underground in the distant mountains. Fast-forward to the 20th century, and the legend was long forgotten and a school was built on top of what nobody remembered was a demon seal. Thus giving him the opportunity to possess students and faculty as he laid out plans for escape and revenge.

• Tatsuya Misaki is basically straight-up evil in Shin'yaku, but in the OG story, he's only under possession. At the end of the story, Nightmare's (temporary) defeat frees him, and Takeru ends up giving him her phone number - with romantic intent, apparently. He never calls, though. Dude seriously missed the opportunity of a lifetime.

Really nice refreshers for me on some of that. I do faintly recall hearing about "Nightmare" being the species name. I tend to mix up that he had a human disguise in OG Inyouchuu, but instead it's that Misaki is possessed there, that makes sense. When yeah he was just a rotten jerk in Shin.

The Kikuka and Ouka intel adds up. I wonder how long Kikuka was captured and tortured by Meioki. I'm not sure. Between their various appearances in a bunch of games, the extra mysterious rare DLC"s (one of them was offline for a year and only available at some Comik event, until it was packaged in one of the newer collections), and Goku dealing with messy time travel... it is hard to figure out the accuracy and full details of their story. I'm skeptical of their mother maybe casting some eternal protection on them, or whatever happens in Goku broke the spell, good or bad. I'm like 80% sure their free of that after Goku. Maybe Suu was just full on guro with some of their scenes (another reason I hate that one so much lol), without them being able to regenerate. I dunno. Maybe a decent chance Suu does so little to the canon story, it's not even worth much. But yeah I guess there's an ever so slight chance next time with see Kikuka and Ouka, they may have finally grown some. They have four sets of portraits, Shoku era, Hanamaru 2 era, Kyou -> Goku, and then Suu. They look youngest in Shoku by far but I think it was just more of a stylistic choice for them there at first, they didn't grow in the next few appearances, but they got more slender and detailed in womanly ways. And Rinko slots in for the token loli.

Sadly Rinko remains a bit of a mystery. A sin they haven't made a Kyou OVA and beyond to get us Anime Rinko. It's amusing they added her into Shin for a brief cameo. But otherwise, all of Rinko's content is still lost in Japanese only material. For now...

Easy takeaway though is that her and Sui become very adorable friends. It's gotta be like mixing fire with water and chaotic in a cute way, I suspect it makes Sui even cooler herself. So I hope to understand their bond someday.

Inyouchuu Lover since ~2005~

I'm still convinced there was precedent to Nightmare disguising himself via shapeshifting, though. In ItA episode 2, he specifically says "I have taken the form of a human" for the sake of tormenting Yamato with seeing Mikoto intimate with another "man." And in the manga, Misaki shows up in the cave, has his way with Sui human-style (now that's a phrase most people don't have a need for!), and then when it comes time to face Mikoto, he appears to shapeshift into Nightmare's form. Though, that could also be Nightmare spawning into the physical dimension at his position using his life force, too - it's mostly offscreen when it happens, so I guess it's not entirely clear.

If I remember the discussions on Anime-Sharing correctly, Kikuka was held captive for about 10 years prior to the events of Shoku. This actually answers my questions about their clothes - the OVA seems to imply that 400 years ago, they were both captured by Meioki while somehow wearing late 20th-century middle school uniforms. Makes a lot more sense that it was a recent event. Other than that ten-year setback, they apparently had their lives pretty much figured out, to the point where they own a mansion and have a butler, I think...?

Incidentally, I did joke that maybe they keep Nokia brick phones in their thigh holsters - since those are immortal too - but according to the detailed playthrough record you sent me a while back, it's actually where they keep their ofudas. The twins are, themselves, already highly skilled demon hunters. I seriously want to know more of their story.

Nightmare can't deny he wanted a piece of Mikoto personally...

The butler sounds right with Ouka and Kikuka. Ouka has a very quirky and unusual personality for being lonely for along time. I wonder if 10 years would suffice. But a butler or someone else would imply she wasn't always alone. I'm not sure. One infamous plot arc with her (probably a bad end that's not fully canon), is some kind of mutual romantic love route between her and the corrupt fat guy in Kyou. She isn't socially programmed to think he's "ugly" and doesn't judge him in that way, so there's a consensual scene and some stuff.

The hair thing with Kikuka rings a bell and must be fleshed out in one of the Goku era DLC's. We do see her with full hair there:

I do think with Ouka at least we get to see how powerful they can be and she is like as strong as the Black Cat's combined, dealing the death blow to Meioki. Whether that's the ultimate good ending I'm not super sure. But it seems like it'd be the one.

Uh oh...

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From the Kyou Gaiden. Kikuka's another that likes him...

So many amazing scenes with them. I am very happy they became main characters pretty much.

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Inyouchuu Lover since ~2005~

I think their depiction in Kowaku is probably my favorite portrait art of the twins. Love that first NSFW-marked pic there haha

• Raikou was created by Yoru, I believe, as per the interview across the Aojiru artbook. Shown in the game, it is not a physical blade - hence passes harmlessly through Takeru's head but kills the demon infecting her brain - and exists in sort of a separate dimension entirely. It's summoned through the little cat keychain plushie, but requires active exertion of its users' magical energy to keep its form, hence why Mikoto can only use it for short periods of time. If I recall, its summoning and usage is locked exclusively to the Shiratori bloodline to prevent it from falling into enemy hands. I would assume Takeru would be capable of using it as well, unless perhaps it's a one-user license of sorts and can only be granted to the eldest child. I would further assume Hatsune once used it herself - which I explored a bit in my fanfic - and wish we had more content about her to tell us more about that.

• The name of the brown-haired girl - a very, very popular character among fans - is Sui in literally all official media and translations that I know of. However, if I point Google Translate/Lens at her name, it often comes across as Mizui. Which is strange, but also very interesting, because "mizu" is a term meaning water... and Sui's magical element is water. Then again, Lens also managed to turn Mikoto into Fukakin, so maybe it's just making crap up entirely.

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Kawaii OVA appearance.

This got me curious to see Hayami was indeed the director of Kowaku no Toki and Hanamaru 2. I used to joke with myself that Ouka and Kikuka were maybe just Aojiru's favorite girls to draw throughout, but we now know that Hayami considered his games to be the same universe. So the crossover makes more sense and was intentional.

Love that he responded shortly to an X PM I sent him earlier this year too around the anniversary. If he stuck around Tinker Bell or goes back (please, I'll use the Dragon Balls wish), seems like he wanted to a do a Kowaku 2:

I hadn’t originally planned to include Momoko in Inyōchū, but at the time I was developing the concept for Chūwaku 2. As part of that, I was considering featuring characters from Inyōchū, and there were also plans to include Momoko as a continuation from the previous work.

- Hayami January 2026 (I feel a quote is hopefully okay, a screenshot maybe less professional).

I was also talking about Mouryou but he clarified he had nothing to do with that one. Which... people have often argued is part of the same universe too and it rightfully looks it. Overall, Hayami is the mastermind to me but maybe I shouldn't blindly discredit anything else like Etsu, Mouryou, etc that doesn't always involve him, they can still be fun installments and feel authentic to the main story/world. It's like overcrediting Kojima games haha, when so many more help him create it. But that certainly makes piecing the fragmented Inyouchuu lore even tougher in what to consider canon and not. 

Great intel on Raikou. 

Inyouchuu Lover since ~2005~

That's a good point about giving every game at least some credit. Etsu's events were largely ignored starting with the next game, for instance, but there's no reason not to at least accept the lore it offered us - and, I mean, it gave us Hatsune.

Also pretty awesome you're still in contact with Hayami to some degree, too. That bit of trivia about the connected universes is pretty cool.

Yeah I think it went both ways - Hayami didn't want to work off of the games he wasn't involved with, and TB maybe respected it in reverse to not add or finish off to his stories either. Making it extra convoluted for us fans worried about the ultimate canon. XD

But hey I'm the guy that looks taking Mega Man lore seriously too... what can I say.

Inyouchuu Lover since ~2005~

I guess that's why they say if the studio won't finish the story, it's up to the fans! I gotta put together more stuff when I have time. Maybe that "Inyouchuu Houkai" idea I shared you a while back.

If you're a big MM fan, you'd probably get along well with my partner's cousin. He's been doing a bunch of Mega Man fanart/OCs and sprite work, and has apparently developed enough interest that other people are now doing fanart of his characters.

Anyway, more lore!

• The White Cat Brigade, explored in a few JP-only games and of course mentioned briefly in Shin, fronts as an idol agency, and there's even art of Rinko singing as an idol (which I'll find and post later). So, a group of singing idols who are secretly demon hunters. Huh - guess what, KPop Demon Hunters fans, Inyouchuu did it first!

• The art from the InyouchuDMM gacha/card game also includes at least one image featuring Takeru in Mikoto's uniform. I'm sure all these images will eventually make it onto the wiki. Kinda makes me curious what situation led to that, though. She's definitely cute in it.

• I had a screengrab of Shoku during my brief test play, and can further confirm that the bathroom and kitchen of the Black Cat apartment are both nice, and the rent is only 15K yen (a bit under $100).

• Hayami's instructions to Aojiru when creating the character of Mikoto - again from the artbook - was pretty much that she needed to be as beautiful as possible (and he certainly delivered on that). Roughly paraphrased from his description of her, "She could easily make it as an idol, if only she kept her mouth shut."

Yeah I think it went both ways - Hayami didn't want to work off of the games he wasn't involved with, and TB maybe respected it in reverse to not add or finish off to his stories either. Making it extra convoluted for us fans worried about the ultimate canon. XD

But hey I'm the guy that looks taking Mega Man lore seriously too... what can I say.

your a megaman fan too? wasn't expecting that! what series do you like? I like every megaman series, been playing them since i was 5 haha. the starforce legacy collection that just came out a little while ago is awesome. Also they were planning on doing a second Kowaku??? and that was going to feature a lot of momo? im kinda sad all we got is that joke ending in Inyouchuu, then again at least that way Momo doesn't have to suffer, after that ending i can only really think of her as canonically someone even Nightmare towers in fear under, which is hilarious and awesome to me.