Swallowtail Butler's Cafe Librarian

お帰りなさいませ 𓂃 ࣪˖ ⋆.˚ ʚїɞ ⋆

Welcome to my blog!! This place is dedicated to sharing information about Butler's Cafe Swallowtail, Tokyo's famous butler cafe that you've probably seen on YouTube. The whole thing goes way deeper than you think!

What is Swallowtail (執事喫茶Swallowtail)?

Founded in 2006 by the K-Books Corporation, Butler's Cafe Swallowtail is a concept cafe situated in East Ikebukuro, Tokyo, Japan. For 20 years, the establishment has continued thriving as a tourist destination and as a local cult favorite.

Despite falling into the category of a "men's concept cafe," Butler's Cafe Swallowtail stands out from others in its genre due to its strong commitment to its concept. The atmosphere is immersive, staff have thorough training and experience, and the culinary offerings are top-notch. Additionally, even if women remain the target audience, Butler's Cafe Swallowtail explicitly welcomes all.

It is not a host club.

You can read more on their official website (after which this blog is named).

What is Butler's Operetta (執事歌劇団)?

A secret often kept from English-language coverage, Butler's Operetta is Butler Cafe Swallowtail's associated underground idol act. They hold concerts, with singing and dancing, as well as theatrical productions of original works. Much of the music and choreography is created by the members themselves.

The current members' names and roles are:

FURUYA - Choreography, Dance

IORI - Script Writing

KAGEYAMA - Choreography, Dance

KUMAGAWA - Composing, Vocals

NOUMI - Choreography, Dance

YURINO - Composing, Vocals

Butler's Operetta was established in 2010. Their participating members have shifted over the last 15 years and they have numbered as many as up to eleven at a time.

Some former members are still employed as regular staff at Butler's Cafe Swallowtail, such as KAGAWA and TAMAKI. Former member SHIINA now serves a roadie-like role. Some regular cafe staff will also participate in Butler's Operetta performances as guests.

You can find their discography, member introductions, and more on their official website!

Who Am I?

Call me Ojousama. Butler's Cafe Swallowtail and Butler's Operetta have been my special interest since fall of 2023. I'm an aspiring Japanese language translator and interpreter, as well as an art, music, and fashion enthusiast. I speak Japanese at a rough conversational, intermediate level.

My first visit to Butler's Cafe Swallowtail was in September of 2023, and as of January 2026 I've now been over 50 times!

I feel that Swallowtail and Butler's Operetta are something special. I feel that they have something more to offer than the average concept cafe or underground idol. I'll dive more into my experiences that explain why I think so in this blog!

I also talk about Swallowtail on my own website, and I can be found on/will follow from my main blog, @ojo-sama.

If you're convinced, consider joining our fan discord server!

お楽しみくださいませ ₊˚⊹ ʚɞ

I don't want to make this post, but the issue is weighing on me and perhaps I'll feel better if I write out my thoughts.

Long story short: generative AI is creeping its way into Butler's Operetta's performances.

It started with the release of their last stage play, "0/O(ゼロイチ) 〜見上げる空は ハルカうららか〜" (Zero/One ~The sky above is distant and bright~) (Title translation roughly done by me) when the sets were all clearly A.I.-generated projections. They were muddled and ugly. Even though I bought the DVD, I haven't watched it because the backgrounds are so distracting. The soundtrack, however, sounds human-made. When this happened, I decided that because the core of the performance, the music and presumably the writing were human, I could chalk it up to execs/designers being lazy and/or wanting to use a ~newfangled~ technology. To this day, awareness in Japan about the harm of AI continues to be low.

Attending their concerts to this day, the set projections appear to be a mix of CGI, photos, and AI.

Then a bombshell. I attended "Anthurium Vol. 8" a spin-off performance series of just the vocalists Kumagawa and Yurino. Yurino performed "時を超えて" (Toki wo Koete) in a new rock arrangement. I thought it was great. Only after did he reveal to the audience that the arrangement was generated by A.I. In the moment my heart sank, and I was gloomy the rest of the performance and the whole night through. AI had infected the artistic aspect of the operation. But since it was a modification done for a spin-off, and not a whole original song or something on an album, I let it go. This was a few months ago.

Soon after, Yurino posts on Hana ni Otome, the supporters-only content site, a "podcast" as I call it, of him discussing the new AI arrangement. He even acknowledged that AI is controversial, but said it was "just to mess around with." While unsatisfying, I was further pacified. Surely, I thought, as an artist, Yurino won't automate his passion.

I did not attend the next edition of Anthurium, Vol. 9, due to my busy schedule. The set list was released afterward: Kumagawa performed a new arrangement of "coordinate." My alarm bells went off. A little while later, Kumagawa posts his Hana ni Otome "podcast," where he performs this new arrangement of coordinate, made to be in a big band style. Sure enough, even though to my knowledge he never says so (I believe he says it was "like Yurino's remix of toki wo koete"), it's AI. The swells and hits are in all the wrong places, and it just obviously lacks human thoughtfulness, as AI often does. As not only a musician but a visual artist, I hoped Kumagawa might be anti-AI. This was all last week.

As of now, these are all the substantial instances I'm aware of (Iori once posted what appeared to be AI generated stickers of his pets, which I think was annoying but benign, and also a long time ago now).

Awareness about the issues with AI continue to be low in Japan. I think it's more often seen as a fun technological toy, as well as a trend. Best case scenario, I hope that like any trend its popular usage will die out, and Butler's Operetta will follow suit. Additionally, the perpetual worrywart that I am, for the sake of my blood pressure I resign myself to restrict my vitriol to the tech billionaires and corporations who are the real villains of this story, and spare the misguided consumer from my ranting.

I can see that I'm making excuses for my beloved idol project. I'm afraid of the future, not only for potentially rewarding lazy business practices, but also the undermining of artistic integrity.

My breaking point will be if they attempt to sell AI or fully-AI-made works. If they automate the entire songwriting or script writing process, that will be it. I haven't ruled out the prospect of writing a firm letter to the management, but it would be a big undertaking to do that in Japanese so I'm holding out. For now, to my knowledge their albums are AI-free, and human-made music and performances are still at the core of their performances. But the fact that there has been a slow increase in their usage of it until now makes me worried what will come.

Report format

Date: 26/05/05

Time: 12:40

Live Report

Door: Kirishima

Butler: Hayama -> Tokito

Tantou: Nakajima

Familiar Faces: Yurino, Hino, Noumi, Furuya, Saiki, Saejima, Yahata, Kubo, Ayase, Shiba, Minowa, Sakura, Uduki

Notes:

Nakajima GOT MEEE he looked at my member card and went "oh you were here yesterday" unless you're paying for my rehab let me be addicted in peace!!

He commented on my coord as I entered you get me

Noumi wanders around watching like a hawk. I think he's monitoring newbie Minowa

Yurino took me back from the restroom. He asked about my outfit and told me about Swallowtail's old fashion collabs.

Nakajima's got a bunch of cute beauty marks I'm glad I can capture now.

Naka liked his portrait he turned so authentic for a moment xD he asked to see more so I showed him my recent Fujinami and Iori

Post Report

When Nakajima pointed out that I'd just been there the day before, I looked away all sheepish, to which he said "it's alright, it's your home after all!" I love when they roleplay the bit. I maintain that my hobbies of lolita fashion and going to Swallowtail culminate into one big hobby of grown-up princess pretend, so I appreciate the participation in my pretend game.

Furthermore, I wasn't really that upset at the comment. Since the menu turns over every month, the footman walks you through the changes. Nakajima was confirming I had already been walked through the new menu and didn't need him to do so again.

When your name is kept on file at Swallowtail, I've noticed the footman wouldn't start using my name until after he'd disappeared with my member's card, seemingly using my card to find an internal record with my preferred name. Nakajima, however, was using my name from the moment I entered through the front door. Very well done.

I commented to Nakajima that Swallowtail has acquired lots of new staff recently, prompted by my first sighting of Minowa in the salon since I first met him at the gift shop in March. Likewise, Minowa's position at the gift shop has seemingly been replaced by a certain Toba.

Nakajima is fun and sweet, but he's quick. It's hard to have much conversation because he seems to always be in a rush. I'm sure I'd be nervous and rushing if I did that job, too.

When Yurino brought me back to my table from the powder room, he thanked me again for coming to the Anthurium show the other day (The "Anthurium" show series consists of Shitsuji Kagekidan's two vocalists, Kumagawa and Yurino, and could perhaps be described as a subunit. I attended a show the week before). I've only ever spoken to Yurino twice before this, once at the aforementioned Anthurium. I was terribly starstruck and stumbling over my words. Though I thought he would simply return me to my seat and be done, he continued talking to me, asking about my outfit. He specifically asked what brand, and I lit up. When I said Baby, The Stars Shine Bright, he knew. I put 2 + 2 together and realized Yurino probably knows a thing or two about J-fashion, so I mentioned that I'm dying to find the old Swallowtail x Metamorphose collab dresses. This prompted him to mention how Swallowtail's done a variety of fashion collabs, specifically citing fashion shows done at Anime Matsuri with Metamorphose, Atelier Boz, and Putumayo. I'd known about Meta and AB, but not about Putumayo. It was super cool to learn Swallowtail history from a veteran.

As Yurino was about to go, I finally remembered to tell him about my Kagekidan nails, which I had removed a few days prior. I pointed out which nail had been his representative white. He said that's nice and that I should show Kumgawa too. Thankfully, Kumagawa got to see the actual nails.

Portrait

Nakajima quite liked the portrait. I think he said that it "`めっちゃ似てます" (totally looks like me). It's my first time referencing without his mask, which was hiding distinct little beauty marks all around his face. I said to him that I was glad to be able to see his moles, specifically calling them かっこいい. He implored I show him more. It means a lot to me when they show increased interest in my drawings.

Report format

Date: 26/05/04

Time: 16:30

Live Report

Door: Hayama

Butler: Munechika

Tantou: Fujinami

Familiar Faces: Saiki, Sakura, Yurino, Kumagawa, Uduki, Ayase, Muroto, Yahata, Munakata, Yonezawa, Kagawa, Tojo, Yamaoka, Shiba, Kubo

Notes:

Fujinami is adorable. So sweet and seems to love the job

He did bring cream and sugar even though I said no but he's cute so it's ok :)

His voice is so cute but so quiet

Fujinami actually asked me for English advice :) soo fun

Post Report

When I arrived at the entrance, Hayama didn't even confirm my reservation name or time, he just escorted me to sit inside. What am I, a celebrity? (laugh track)

Fujinami is an exemplar staff. He is committed and enthusiastic. You can tell when a staff at Swallowtail loves the job and really loves playing the bit.

Fujinami's also just plain adorable. His voice is very high and light, it's very unique.

My first encounter with Fujinami, I was with a friend speaking English when he approached us of his own accord. He is very enthusiastic about language learning.

On that note, I asked him how his English studies are going and if he's seeing lots of foreign guests. Much to my delight, he asked if he could confirm vocabulary with me, and then proceeded to actually do so. When I asked to be shown to the powder room, he asked how he'd express that he'll take my bag in English. I love sharing and comparing language, so this was really fun.

He asked about my Golden Week plans, I mentioned that I spent the first day deep-cleaning my home (my second home where I don't have servants to clean for me, that is ;) ). He agreed that a clean home is a clean mind.

Portrait

Fujinami was happy with his portrait. I struggled with it more than usual, taking my whole 100 minutes to finish it. I still didn't quite capture him. Fujinami looks very sweet and friendly, but I'm afraid my portrait makes him look sly. Combined with his voice, the real person has the air of someone who wouldn't harm a fly.

Report format

Date: 26/05/03

Time: 11:30

Live Report

Door: Shiba

Butler: Tamaki

Tantou: Iori

Familiar Faces: Kanazawa, Kumagawa, Uduki, Noumi, Yonezawa, Furuya, Tojo, Nozaki, Muroto, Saiki, Kirishima, Ayase, Saejima, Yamaoka

Notes:

HOLY PEAK?

I'm tweaking so bad I had to take my propanolol [sic]

4/6 Kagekidans + Tamaki butler wtf is going on??? Pity reset

A girl next to me had her birthday celebrated by Iori and Kuma, so happy for her <3

so much I wanna tell Iori...

The end of the page is decorated with a doodle of a sloth.

Post Report

A visit 927 days in the making. It's not my first time being seen by Iori, however, the first time was with a new friend, so I felt compelled to contain myself. The second time, he tagged in at the end of my visit. The third time, he tagged out at the start of my visit. This was my first time being seen by him on my own.

Propranolol is a beta blocker medication. I take it as-needed for anxiety-related tachycardia, and as-needed isn't very often. Toward the end of my visit when I visited the powder room I had to stop and process.

The topic usually turns to language when I'm with Iori. As he read off the menu to me, he stopped at the rose-flavored scone, written out in kanji (薔薇) to comment on how complex the writing is. He pointed to each item he read very clearly

He reckoned I was on break from school for Golden Week, which was true. I tend to fill up Swallowtail visits during my breaks from class.

Noticing my sketchbook, he asked to see my portraits. I showed him the previous day's Muroto, as well as older portraits of Kubo and Nakajima. He praised me nicely, commenting that I captured their likenesses, which made me very happy.

I left my choice of teacup up to him. He brought me Richard Ginori's Oro Di Doccia in magenta. The cup's name deems it magenta, but it's more of a red. As such, Iori cited my attire that day as his reason for choosing it. That's a pretty standard protocol at Swallowtail, so I wasn't very surprised, but I was delighted to inspect the cup further and see whimsical depictions of roosters.

This month's afternoon tea set comes with a serving of fish. I ordered it despite knowing I don't like fish, as there have been occasions where I've had fish at swallowtail that I could manage. Unfortunately, this serving was not manageable, and I left it after one bite. When Iori took my plate, he noticed, and asked if I don't like fish. I apologized, saying it's such a shame I don't like fish in a country with so much delicious seafood. He was very kind about it. (I felt additionally embarrassed since Iori himself is a skilled cook, and shares his dishes, often including fish, on his social media page. Someone like that finding out I'm picky is a bit extra embarrassing.)

I always swore I'd order the sherbet when I was finally seen by Iori. I ordered this month's new matcha milk flavor. Iori and I talked about matcha; I enthused about how much more affordable it is in Japan compared to the US. He rightly pointed out that overseas demand has created a shortage, but that May is the month in which tea is harvested.

Swallowtail's sherbet is prepared tableside by your waiter. In a large can, he mixes the cream with a container of frosty liquid. Having always wondered, I asked him what it was. He replied in Japanese, making me tilt my head. He translated - liquid nitrogen. I was very impressed he knew that off the top of his head. He's a bit begrudging to have full English conversations, for which I don't blame him, but the way he knew that word immediately put a stop to any doubts I had about his ability.

Continuing the topic of Japanese words for scientific compounds. I mentioned it was thanks to him that I remembered the Japanese words for "citric acid" and "baking soda." These words were used in an old YouTube video on the swallowtail channel. He seemed pleased I remembered.

In the end, he didn't come back to see his portrait before it was time to go, so it was left for next time. I rushed to cram my sketchbook back into my purse for departure, leaving part of it adorned with a sticker of Iori exposed. Tamaki commented on it, thinking it was Yurino at first, until Iori said "it's me!" I missed the exact words exchanged, but it was delightful to see the closeness between Iori and Tamaki. I've mentioned before that Tamaki is a former Kagekidan member, so while there were many years of these two performing together, to see them like this now that Tamaki has stepped out of the limelight was very special.

I'm dissatisfied with myself for not telling him all the things I wanted. It's hard to relax and talk naturally.

Portrait

I'm very pleased with the result of this portrait. I will be showing it to him first thing next time I see him.

I do spend a lot of my spare time staring at pictures of his face, which helps. (laugh track)

Report format

Date: 26/04/26

Time: 18:05

Live Report

Door: Tokito

Butler: Shiba -> Hayama

Tantou: Muroto

Familiar Faces: Hino, Saiki, Yahata, Tojo, Kagawa, Inui, Saejima, Noumi, Furuya, Uduki, Kobayakawa

Notes:

I got a strange wave of guilt when I entered, feeling embarrassed for the frequency of my visits, then I remembered making fun of an autistic person for their special interest is ableist and I feel better :)

Post Report

I ordered this month's special sherbet, "diamond martini." Keeping with the name, it was garnished with glittery sprinkles. I asked for it without alcohol, so the taste was like bright citrus.

Since I neglected to type up this report until now, I don't remember much to report.

Portrait

I mentioned in another report that I like to capture my subject's unique details. I went out of my way to depict Muroto's cauliflower ear as I find it appealing. Muroto seemed a bit puzzled by my drawing, but said he liked it and that he was pleased.

I'm a bit dissatisfied in my ability to capture his likeness otherwise.

Report format

Date: 26/04/19

Time: 16:40

Live Report

Door: Tokito

Butler: Shiba

Tantou: Saiki

Familiar Faces: Kageyama, Furuya, Yahata, Inui, Muroto, Uduki, Nozaki, Ayase, Nakajima, Yamaoka, Tojo

Notes:

No notes today.

Post Report

No notes today. I'm making this report despite it being empty for my own memory.

Portrait

No portrait this time.

Kumagawa and Yurino stall through technical difficulties with an impromptu a cappella performance of "In House Rule." 2025.11.15 "Autumn Concert" at Tōbu Skydeck.

*Recording was permitted at this event.

Report format

Date: 26/04/18

Time: 16:40

Live Report

Door: Kirishima

Butler: Kagawa

Tantou: Iori -> Kobayakawa

Familiar Faces: Nakajima, Kubo, Inui, Hino, Furuya, Sakura, Fujinami, Ayase, Munakata (???), Yamaoka, Yahata, Saejima

Notes:

Iori takes me in then immediately taps out. It feels weird. It's strange. Especially since he's still working other tables.

Kobayakawa is sweet. He's quitting soon, so I'm glad to see him again. He even remembered that he hasn't tantou'd for me since last year.

I'm really down. I can't shake the feeling that Iori had his placement changed on purpose b/c of he's tired of me (the audience may want to know that, other than my obvious attachment issues, this visit was preceded by recurring Kagekidan events, so I'd been around him more than usual)

He came back and chatted to me. I think he noticed how pensive I looked as he specifically sounded like the change was out of his control. If he was really tired of me he wouldn't have done that.

Post Report

Munakata's name on the Familiar Faces list includes the (???) because it was my first time seeing him working in the tea salon when he was once a gift shop-only staff. There are cases of new hires training at the gift shop before starting work in the main cafe.

The audience need not be concerned with my mopey comments. Iori being my favorite, I'm a bit extra prone to over-analyzing. I am otherwise no fool regarding the idol-fan dynamic we have.

Indeed, Iori tapped out of serving me as soon as I'd placed my order. A shame alone, worsened by the unknowable nature of Swallowtail's staff scheduling. I figured that Iori's shift was done and he was leaving me to take a break or go home. Alas, his responsibility shifted to the table directly next to me. I am a naturally jealous sort, so this added insult to injury, but once again I reassure the audience that I am much better about it than I once was.

Portrait

I waited to long to type up this report so I don't remember if Kobayakawa had anything to say about his portrait. I'm glad I got to capture him one last time before he left.

One of the reasons I love doing portraits is I love to focus on an individual's unique little characteristics. I love Kobayakawa's jaw.

Also me when the function got bromides: shiiiiiiittttt yall got bromides? #mybromides

TOXIC

Butler's Operetta "Spring Concert" 2026.04.11

Butler's Operetta at Château de Foix, southwest France, summer 2025

April's full of Kagekidan events, so I knew I needed to go Kagekidan theme for this month's nails.