Japanese rock band Aooo recently dropped its second studio album called Rooom. The group features a dream-team lineup of four members with solid backgrounds: ex-Akai Koen vocalist and solo artist Riko Ishino (Vo.), Vocaloid producer and singer-songwriter THREEE (Gt.), Hikaru Yamamoto (Ba.) known for her support work with YOASOBI and more, and Tsumiki (Dr.), who has crafted tracks including “Phony,” MAISONdes’ “Tokyo Shandy Rendezvous,” and Hoshimachi Suisei’s “BIBBIDIBA” while also serving as guitarist and drummer in NOMELON NOLEMON. 

The record holds everything the band has built and nurtured since forming in 2023 and brims with ambition for what lies ahead. Billboard Japan spoke with all four members to explore the story behind the album, the band’s current headspace, and the blueprint they’re drawing together.

After your Live Tour “BAKUBAKU” in fall 2025, you held the Special Live 2025 “Bazoooka” show at Tokyo Garden Theater in December, where you debuted “Star Sign,” a track included in Rooom. The track feels like a natural expression of the band’s unity and something of a milestone for Aooo.

Riko Ishino: Toward the end of the “BAKUBAKU” tour, we were all eating together and talking about how the three consecutive releases had this sharp, hard-hitting energy, and that we wanted to show people something in a completely different direction. And we were like, “It’s been two years since we formed, so why don’t we all write the lyrics and music together, looking back on our relationships and everything that’s happened in Aooo?” It just naturally clicked for all four of us, one “Yes, let’s do it” after another, and that’s how the song was born.

Hikaru Yamamoto: Aooo has always made music collaboratively, even while dividing up roles, and I really wanted to distill each of our four perspectives on the band into a single song. Since the Garden Theater show was a milestone where we were performing our entire catalog, I wanted to close it out with a new song the four of us had written together that captured the view from where we’re standing now and our desire to keep going.

Tsumiki: The chorus Ishino wrote felt like a letter to the members. That pulled me in and I wrote the pre-chorus section from there. There are so many moments of resonance when we’re creating music or building shows together, so I wanted to write about the miracles and coincidences that exist within something that also feels inevitable.

Yamamoto: Ishino writing the line, “Because I found somewhere I belong” meant a lot to me. Right around the time we were working on the song, we all went into the rehearsal studio together, and THREEE made this completely absurd mistake he never makes. [Laughs] A total fluke, and we all just lost it laughing. And in that moment I had this sudden thought, “Maybe when I’m at the very end, this is the kind of thing I’ll look back on, just laughing at something ridiculous with everyone.”

That’s basically the verse-one lyric, word for word.

Yamamoto: Before that, I’d vaguely assumed that what I’d think back on at the end of my life would be something like finally standing on a stage I’d been pursuing or playing in front of a massive crowd with bright lights behind me. But that moment when we all laughed completely changed that. At the same time, it all suddenly made sense. Maybe that’s just what Aooo means to me.

THREEE: I wrote my section to follow on from what Hikaru wrote for the first verse. Constellations only become shapes when you connect individual stars, right? Everyone in Aooo has their own solo career, so each member is shining on their own, and I want them to keep shining. So I was thinking how when the four of us gather, that’s what becomes the shape called Aooo.

Ishino: Having been part of Aooo for two years, I’ve had this real sense of finding an incredibly comfortable place, somewhere I can feel settled. Every member is deeply specialized in their field, and because each of them has a solid solo career, they’re independent, people you can genuinely rely on. My ideal for a band has always been a relationship built on mutual trust, and the fact that it happens naturally here, without anyone even thinking about it, is part of why Aooo feels like somewhere I’m safe.

There have always been bands formed by experienced artists, but in Aooo’s case, partly by virtue of your lineup, you strike me as having both the sharpness that comes from seasoned professionals and the kind of pushing-each-other-forward, rival-energy you’d find in a shonen manga.

Ishino: If you feel that way, I think the reason is largely down to THREEE and Tsumiki. [Laughs]

Tsumiki: [Laughs] THREEE and I debuted as Vocaloid creators at almost exactly the same time. We were trading No. 1 spots on the charts, so asking him to start a band with me was one of the biggest things that’s happened in my life. And Ishino and Hikaru are both artists I’ve respected for a long time, so they definitely fuel my creative drive.

THREEE: I’d just branched out from Vocaloid producing into singer-songwriter work when Tsumiki reached out and brought me into Aooo. I’d always worked alone before, so the ideas, values, words, and creative work that each person brings, born from their own individual paths, are all exciting. So I’m always thinking about how to write something that gives everyone that same spark, that stirs their creative drive. There’s definitely a, “So, what do you guys think?” vibe when I drop a demo. [Laughs]

Tsumiki: Building on what Ishino said, being able to rely on the members is huge. Onstage, I can be at peace just existing as the drummer because Ishino is so solidly the face of Aooo. I feel a bit embarrassed saying this, but I think standing at the front with these members behind you is really hard. The fact that you can feel Ishino stepping up there with a real vocalist’s conviction and sense of responsibility is what makes Aooo work. The reassurance of knowing she’s carrying the band is immense.

Ishino: I think that might be the first time you’ve ever complimented me. [Laughs]

Yamamoto: Everyone’s always thinking it, they just don’t say it out loud! [Laughs]

THREEE: The band has grown a lot now, but it all started with Tsumiki going, “Hey, want to come jam at the studio?” and me saying, “Sounds fun, I’m in,” without a second thought. My motivation in Aooo has been the same from day one — it’s fun. The spark I get from the other members, the way I get to respond to what they’ve made on guitar… all of it is fun. And I feel like those experiences are feeding back into my solo work, too.

Your Live Tour “RINGRING” includes dates in Taipei and Seoul, and I take it Aooo is putting more energy into international shows going forward. Was that appetite for performing abroad something all of you already had?

Tsumiki: From the time I started making music, I’ve always wanted it to reach as wide an audience as possible, regardless of nationality or age. I want people to feel free to enjoy Aooo’s music and everything else we make in their own way, and I love watching how listeners respond. In South Korea, for instance, the parts that audiences sing back aren’t always the ones you’d expect. I guess the lines that stick vary from country to country. Those moments where the reaction catches you off guard are fascinating.

Yamamoto: In my case, I started uploading performance videos on YouTube because I wanted as many people as possible to hear me play. Even back then, I’d get comments in foreign languages mixed in with the Japanese ones, and that really drove home in a tangible way that people in other countries were actually watching. It means a lot when someone who’s been following my videos leaves a comment saying, “You’re finally coming to our country,” and I love that moment where you get to say, “Nice to meet you” under different circumstances.

THREEE: We’re happy to have more opportunities to actually meet international fans face to face at our shows. At the same time, it’s something I wrestle with in terms of how to approach writing. The phrasing in my lyrics can feel a bit convoluted even for Japanese listeners, so I find myself wondering, “How are these words landing for someone overseas? What should I be doing going forward?” I’m hoping that uncertainty ends up pushing my work somewhere better.

Ishino: Both Taipei and Seoul are headlining shows, so the fact that people can spend plenty of time with us means a lot. The chance to properly deliver everything we’ve built across seven shows in Japan — and really, over nearly three years since we formed — is pretty valuable, and I’m grateful for it. I want to make sure everyone leaves feeling glad they came, and that the experience stays with them.

What kind of vision do you have for where the band goes from here?

Tsumiki: J-pop contains rock, pop, and all sorts of other genres within it, so it’s composite by nature. Since Aooo is already doing that, I think we’re capable of making music that can represent Japan. That’s what I want to keep working toward, and I want to make Aooo a band that can stand for Japanese music on a global scale.

Yamamoto: We started doing what we love with people who really excite us, and as a result, more and more people have found (our music) interesting and we’ve started crossing genres. So I have this feeling that we’ll be able to keep enjoying it all together, different opinions and all. This wasn’t a business project and came from a completely genuine place. I’m excited for what we confidently say, “This is Aooo!” to keep spreading, and I really hope it does.

THREEE: I share the vision Tsumiki and Hikaru described, but what excites me most is the idea of everyone bringing what they’ve absorbed into Aooo and setting off a chemical reaction that produces something new. I want our work to stay rooted in what we want to do. As a band, I want to enjoy whatever comes out of what we all bring to the table.

—This interview by Sayako Oki first appeared on Billboard Japan

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