Music

On Oct. 4, the digital maxi-single VORTEX was released. This single, which contains three songs, features vocalist Setsuko of Kuhaku Gokko.
The songs “VORTEX” and “karma” are the opening and ending themes of the TV anime series Mechanical Arms. In the show, protagonist Hikaru Amatsuga meets Alma, a mechanical life-form shaped like an arm, and becomes embroiled in a series of incidents. Billboard Japan spoke with Setsuko, Okamoto (the original planner and director of Mechanical Arms), and Hiroyuki Sawano (the songs’ composer, arranger, and producer) about their impressions of “VORTEX” and “karma” and the creation of these songs.

Setsuko and Hiroyuki, what are your impressions of each other’s music? What kinds of things did you think about during your musical collaboration?

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Setsuko (Kuhaku Gokko): When it comes to Hiroyuki, I’ve listened to his work as SawanoHiroyuki[nZk] more than his soundtrack work. [nZk]’s songs have the same musical foundation, but the impression they make changes a lot depending on the vocalist. I feel like that’s because when he writes the music, he makes space for the vocals. So then the question becomes, what should I do in that space set aside for me? To be honest, I wasn’t feeling very confident when he first reached out to me.

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Hiroyuki Sawano: My impression of Kuhaku Gokko, which Setsuko’s a member of, is that their sound has an edge to it. “VORTEX,” (the anime’s opening theme song) in particular, has a rock-like rhythm, so I was looking forward to see how Setsuko would express herself. I’m more interested in how vocalists’ voices will sound within my songs than in the sound of the vocalists’ voices themselves. In that sense, I was dealing with the unknown, but that’s part of what makes it interesting.

Okamoto, you’re the original planner and director of Mechanical Arms. What were your expectations for the collaboration between Setsuko and Hiroyuki?

Okamoto: I was hoping that with the opening theme, they’d make something that depicted the work at the surface level, and with the ending theme, they’d delve deeper inside it. I’ve listened to Hiroyuki’s music before, in my everyday life, but I’m embarrassed to admit that I didn’t know much about Setsuko’s Kuhaku Gokko project. But precisely because of that, I was really looking forward to hearing what kind of world the two would create when they combined their musical sensibilities. Both the opening and the ending themes far surpassed my expectations. I feel like they’ve expressed things that we weren’t even able to express in the anime’s art and scenarios.

Hiroyuki, you said that there were rock elements to “VORTEX,” the opening theme. To me, it feels more like dance music. It feels to me like you tried to give it a straightforward feel.

Sawano: It has a dance music-like groove, as you said, and I also tried to mix in some rock and electro elements. Depending on how you look at it, this anime has parts that can be seen as comical, but I feel like the real highlights are the stylish battle scenes. I wanted to express that coolness in the sound of the song.

Setsuko: My first impression when I heard the demo was also that it was simple and cool. That came as a big surprise. What I mean by that is that my own impression of Mechanical Arms was that it’s a very comical anime. Of course, the battle scenes are really stylish, but the everyday scenes have a comedic pace to them, and there’s a certain cuteness to the shapes of the mechanical elements and way people move. So my overall impression was pretty much the same as Hiroyuki’s. I didn’t expect the music to be so solid, so I was like, “What kind of vocals should I be adding to this?”

The instrumentals in “VORTEX” are straightforward and a little inorganic, but your vocals, Setsuko, passionately wind through the song. I think the elements are incredibly well-balanced.

Sawano: I wanted the vocals to have a bit of heat to them, a bit of energy. But it’s not like I was initially trying to go for a gap between the heat of the vocals and the coolness of the music. That was just the result of leaving the singing up to Setsuko. She’s the one responsible for creating that balance.

Setsuko: At first, I used a cold tone in everything leading up to the chorus, and then ratcheted it up when I hit the chorus. But then Tsubasa Harihara, another member of Kuhaku Gokko who’s an ardent fan of Hiroyuki, said “Even if you go with a cold approach, give it the feel of wearing an oversized hoodie, with the hood pulled low so you can’t see your face, walking quickly with your eyes downturned.” That got me thinking that the song would work better if I approached it with more of a hip-hop mindset, which is why I ended up singing it with a rap battle feel.

Okamoto, what did you think upon hearing the completed “VORTEX?”

Okamoto: Like everyone says, it’s a simple and stylish song, but that also made it hard to put pictures to. As Hiroyuki mentioned, this song focuses on the cool aspects of Mechanical Arms, as epitomized by its battle scenes, so when I worked on the video, I also approached it with a rap battle feel. But Mechanical Arms also has comical elements, so I wanted to be a bit playful, too. I tried putting in some comical scenes in the opening video, and they ended up also going really well with the song. The song is simple, but I could also feel a lot of depth to it.

What about the ending theme, “karma?”

Sawano: I handle the incidental music in Mechanical Arms, too, so to tie in the incidental music with the theme song, I wanted to synchronize the main theme of the show with either the opening or ending themes. Ultimately, I decided to use the main theme melody in the ending theme, “karma.” As far as the lyrics, the opening’s mainly in English, but I wanted the ending to be in Japanese. SennaRin wrote the lyrics for “karma,” and I’ve long found her Japanese lyrics to have a unique and interesting aesthetic. She’s pretty close in age to Setsuko, too, and I thought it would be best to have someone of similar age sing it.

Setsuko: Partly because “karma” is a ballad, I was able to sing in the way I usually sing, and going into pre-production, I found it easy to put emotion into my singing. I didn’t struggle as much as I did with “VORTEX.” I was also able to sing the way I wanted when we did the main recording.

Okamoto: I found “karma” to be hard to create animation for, in its own way. I wasn’t in charge of the ending video. Other staff was responsible for that, but I have a vivid memory of the staff thinking about the meaning of the lyrics, getting totally stuck, and saying “I just can’t do it.” I told them “Don’t think so hard about it. On the surface, it’s a simple song, so why not focus on the simple parts?” I remember the whole thing really threw them for a loop.

Okamoto, as the original planner and director of Mechanical Arms, how did you interpret the lyrics to “VORTEX” and “karma”?

Okamoto: I thought trying to analyze them too deeply would be a bad choice, so I try not to think about them too hard (laughs). That said, it’s hard not to think about them. For example, both in terms of its sound and its lyrics, “VORTEX” gets the listener amped up, and then suddenly leaves you feeling empty. Hikaru, the main character in Mechanical Arms, has a lot of internal struggles, and is kind of a negatively-minded character. Alma, on the other hand, is extremely bubbly, and she supports Hikaru, but it sometimes seems there’s just nothing really to him. I think the song expresses these characters really well. It’s very impressive. With “karma,” once you start thinking about the lyrics you could just go on forever, so I’d rather leave their interpretation up to the viewers. I don’t really like when creators push their interpretations, so I chose not to think about it too much myself.

Setsuko: “VORTEX” and “karma” are opposites, but there’s a very strong feeling of connection between them. I think that connection reflects the connection between the characters of Hikaru and Alma. As Okamoto said just now, Hikaru and Alma complement each other, and it feels like “VORTEX” and “karma” do, too, while at the same time mirroring the story of Mechanical Arms.

Okamoto: The two songs convey the essence of Mechanical Arms really clearly. Like, if someone were to ask me “What kind of anime is Mechanical Arms?” I could just tell them “listen to the opening and ending themes and you’ll understand.” The simple-but-complicated, or the complicated-but-simple nature of the songs, in particular. I put a lot of thought into the creation of Mechanical Arms, but I tried to keep the ultimate finished product simple. To me, it feels like Setsuko and Hiroyuki have expressed that same thing directly, through their music.

—This interview by Hikaru Sudo first appeared on Billboard Japan

YOASOBI celebrated its fifth anniversary on Oct. 1. The J-pop duo, consisting of composer Ayase and singer ikura, launched its career in 2019 as a group that turns creative writing into music. The “Idol” hitmakers have since released numerous hit songs and gained popularity that transcends generations and borders, expanding their reach worldwide as one of the biggest breakout J-pop acts in recent years. How did YOASOBI cement its current position as a musical sensation like no other? Let’s take a look back at their journey.

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YOASOBI originally formed for a project by the online creative writing site “monogatary.com,” run by Sony Music. The pair’s debut single, “Yoru ni Kakeru” (“Into the Night”) is based on an original short story by Mayo Hoshino entitled “Thanatos no yuuwaku” (“Seduction of Thanatos”) that won the grand prize in the Monocon 2019 competition hosted by the site. At the time, Ayase was a songwriter who released music online as a “vocaloid producer” (vocalo-p), and ikura was a solo singer-songwriter releasing music under the name Lilas Ikuta. The two artists got together for the YOASOBI project and released the music video accompanying their debut track on YouTube in November 2019.

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As the above introduction suggests, the members of YOASOBI initially had no idea they would become as successful as they are now, since the unit formed as part of the online website’s project. At first, they didn’t even know whether they would continue to work as a duo in the long term. But the appeal of their music spread naturally and the music video for “Yoru ni Kakeru” sailed past a million views in just a month after it was released. This is an exceptional number for a new, unknown act.

The YOASOBI phenomenon kicked into full swing the following year. The reaction that had spread rapidly online was also picked up by television and other media from around April, and the buzz expanded into the mainstream. “Yoru ni Kakeru” made it into the top 10 of the all-genre Billboard Japan Hot 100 song chart for the first time on the list released Apr. 29, 2020. It continued to stay in the upper ranks throughout the year and also took the top spot on the year-end Japan Hot 100. The breakout duo also performed for the first time on NHK’s Kohaku Uta Gassen, the prestigious annual New Year’s Eve live music extravaganza.

One of the reasons why the duo’s music gained popularity so quickly was probably the atmosphere of the times. Many people were spending time at home due to the pandemic and the number of those enjoying online entertainment increased. The distinctive animated music videos were also a factor. But it goes without saying that the biggest factor in their success was the power of the music itself. In 2020, YOASOBI released five songs in quick succession, including “Tabun” and “Gunjo.” The songs varied in taste, but Ayase’s signature, catchy melodies and ikura’s vivid vocal expression were demonstrated in each, and the group established its unmistakable pop style.

YOASOBI’s breakout success continued. In 2021, they moved beyond the buzz around a single release and focused on showcasing their appeal as artists. The group worked on high-profile tie-ins including including the dark, electro-pop number “Monster,” featured as the opening theme of the anime series BEASTARS Season 2, and released a number of singles that expanded their musical range. In July that year, they dropped the English version of “Yoru ni Kakeru” called “Into The Night,” which fans noticed had lyrics that sounded like Japanese in places.

YOASOBI’s live performance debut was also a major turning point for the duo whose activities initially took place mainly online. In February 2021, the pair held their first live show — entitled KEEP OUT THEATER — at a building under construction in Shinjuku, Tokyo (the current Tokyu Kabukicho Tower), filmed without an audience and livestreamed for viewers at home. Their headlining solo concert at the historic Nippon Budokan in Tokyo in December that year, called NICE TO MEET YOU, became the duo’s first show in front of a live audience. 

The hitmakers further expanded their activities in real-world settings the following year. In August 2022, they took the stage as headliners at their first summer music festival, ROCK IN JAPAN. In December, they performed for the first time outside of Japan at 88rising’s Head In The Clouds festivals held in Indonesia and the Philippines. That same year, they collaborated with four Naoki Prize-winning authors for a project called Hajimete no (“…for the first time”), and their song “The Blessing,” released in October, was featured as the opener for Mobile Suit Gundam: The Witch from Mercury Season 1 and became a huge hit.

In 2023, YOASOBI scored its biggest hit to date with “Idol,” featured as the opener for the anime Oshi no Ko. Released in April, this single quickly became a sensation immediately after its release. It held the No. 1 spot on the Japan Hot 100 for a whopping 22 weeks, with 21 of those weeks in succession from the chart dated April 19 to September 6, 2023. This is an all-time record for any act in the history of Billboard Japan’s song chart, and naturally the track also topped the year-end list for 2023. The song’s popularity spread to countries around the world, and it reached No. 1 on Billboard’s Global Excl. U.S. chart dated June 10, becoming the first Japanese-language song to top this list.

The duo followed up that hit with another, releasing “The Brave,” the opener for the TV anime series Frieren, in September that year, and the momentum of YOASOBI’s rise to superstardom reached its peak when the group’s debut track “Yoru ni Kakeru” became the first Japanese song to collect a billion streams (it later reached 1.1 billion on May 29, 2024).

The pair also grew remarkably as artists through their powerful performances on stage. In May 2023, they hit the road for their first headlining domestic arena tour, and in August, they performed for fans in the U.S. for the first time at Head In The Clouds Los Angeles. From December 2023 to January 2024, the group toured other Asian countries. The enthusiastic reaction from the crowds in each city must have given the two artists a great deal of confidence.

This year, YOASOBI continues to take on new challenges. In April, they took the stage at Coachella, and also held their first headlining show in the U.S. In August. They also performed at Lollapalooza, steadily expanding their reach in North America. YOASOBI’s first headlining dome concerts in Tokyo and Osaka are planned for October and November, and another run through Asia is set for December to February next year. Music-wise, they released a new song called “UNDEAD” in July. Featured as the theme for the anime Monogatari Series: Off & Monster Season, the latest track’s musical style is even more aggressive and chaotic than before, showcasing a new musical direction for the pair. 

YOASOBI’s five-year journey has been unprecedented, and their success has ushered in a new era in J-pop culture. The hitmakers have adhered to the initial concept of turning creative writing into music, meaning all of their songs, including ones written as tie-ins, continue to be based on original narratives. Each song has its own story, organically linking with other works including anime and films, and can be enjoyed in many ways from different angles. This is one of the true joys of YOASOBI’s music, and the breakout duo will surely show fans new horizons in the future.

—This article by Tomonori Shiba first appeared on Billboard Japan