Original articles on modelpress (Part 1 & Part 2)
Published by modelpress Editorial Department on August 9, 2025

Translated by OP

JO1's Shiroiwa Ruki: "I'm not cut out for this"; At a time when he wanted to quit, fans "saved [his] life as an idol and entertainer" and became his reason to live [AS ONE Interview, Part 1]

The feature-length animated film AS ONE

The film is an adaptation of the arcade game Starwing Paradox, and features a completely original story about the encounter between Yō, a high school student and aspiring musician on Earth who struggles with an uncertain future, and Rako, a robot mechanic from a faraway planet called Meguriboshi. Shiroiwa voices the protagonist Yō, and, under the name RUKI, has also written his first solo theme song "Meguriboshi" for the film.

Sadamoto Yoshiyuki returns from the game to design the film's new original characters. The film is set along the game's established universe and was developed by the production team and scriptwriters based on a concept by director Shizuno Kobun.

The reason he didn't tell the members about his first voice acting role

This is your first time taking on the role of a voice actor. How did you prepare for it?

I like anime, so I've been watching lots of it all this time. But after I decided to become a voice actor, I went back to watch it again from an actor's perspective to study and put myself in the right mindset.

How did the members react when they learned about your first voice acting role?

I didn't tell them at all (laughs). We were pretty busy with the world tour and all, so I didn't think I could ask them for advice or burden them during such a stressful time. I decided to do the best I could then.

Mamehara Issei, in particular, always looks forward to the members' works, doesn't he?

He does! The only thing out right now is a short trailer, so there's not much to talk about. But I think he's seen it. Maybe he'll come and share his thoughts on the radio or something once it's out in full. I always look forward to it!

How did you feel when you heard that SUPER EIGHT's Maruyama Ryuhei was your castmate? You played SUPER EIGHT's "Ai Deshita" on your radio show All Night Nippon X!

I was incredibly happy when I heard about it. I hadn't imagined him appearing in a work where I was the lead. And I never thought I'd get to work alongside him, especially back when I was a student. It truly is an honor.

Life's 180-degree turn after joining JO1

In the film, Yō and Rako transcend dimensions in a fateful encounter. Could you tell us about a fateful encounter in your own life?

A member of the production team contacted me after seeing my self-produced song "Himawari". If I hadn't created "Himawari" back in school, then I wouldn't have chanced upon this movie. I felt like it was almost certainly fate and that I was destined for this film. That's why AS ONE and "Himawari" are fateful encounters for me.

The audition show PRODUCE 101 JAPAN also seems to be a fateful encounter. Was there any change after you joined JO1?

My life made a 180-degree turn. Acting, voice acting, radio, and so on — I think I got to do all sorts of work because of my group activities. Being part of JO1 has allowed me to experience things that wouldn't have been possible in an ordinary life.

Past struggle with the gap between ideals and reality

Receiving the offer because of "Himawari", you must have really felt the connection between your past and current work in that moment.

Naturally, the time before I joined JO1 was full of difficulties, but there was a lot even after debuting, too. To be honest, I've had a few rough patches where I felt disheartened and drained, where I thought things like "I'm not cut out for this" and "I don't deserve to stand in front of people". But I'm glad that I kept at it without quitting. It was thanks to the messages and enthusiastic support from my fans that I was able to get back on my feet.

There's a reason I often thank the fans: They saved my life as an idol and entertainer, and breathed new life into me. I owe it to my fans for getting me through the few turning points I've faced.

In the documentary film JO1 THE MOVIE: Mikansei -Go to the TOP- (2022), you also said you were thinking about quitting JO1 after two to three years.

I felt more and more that "I'm not cut out for this." Now, I can prove myself by standing on stage, making the audience smile and hearing their cheers. But back then, I went through two years without really feeling like I had debuted. It was then that I thought a lot about my future. "Am I honestly okay with the way things are?" "Am I really helping anyone?" My image of idols was so incredibly far from reality that it troubled me.

Did things start to change once you could perform in front of an audience?

That's truly how it was. If OPEN THE DOOR hadn't been an in-person concert at that time, I probably wouldn't have been able to get back on my feet. That's why I think of the fans as my source of strength to persevere and get back up again, even when I'm at my lowest. I'd thought that way even before debut, but it was then when I felt a renewed sense of it. And because of that, I want to keep expressing my gratitude to them for letting me to be where I am today.

The "key to making dreams come true"

A lot of modelpress readers are out there pursuing their dreams. Would you tell them your "key to making dreams come true"?

I think everyone probably struggles at some point in life, just like I did back then. So first, I want them to not think things like, "I'm the only one stuck" or "I'm the only one struggling". My way of thinking has changed a lot recently. I realized no matter how much you think about it, ultimately no one knows the answer. You can ask all you want for advice, but it's impossible to see the future. So, what's important is to think things through. Finally, you should consider "What do I currently want to do?" and "What excites me?" I'm convinced that the choice you make there should be your answer. I want to embody that sentiment from now on, and to tell them, "You're not alone", "let's persevere together".

The changes Shiroiwa Ruki felt after seeing Kinjo Sukai return from hiatus: "Didn't always get through to those around him"; The members are "comrades in arms" [AS ONE Interview, Part 2]

JO1's Shiroiwa Ruki (27) sat down for an interview with modelpress for his first voice acting role in the feature-length animated film AS ONE, which will be released on August 22. Following the first half of the interview, which looked into his period of struggle and how JAM (name for JO1's fans) saved his life as an idol, in this second half, he talks about his feelings toward the members and reveals what was once difficult to say about the obstacles he's faced in the past.

[omitted redundant section about the film]

Feelings after seeing Kinjo Sukai return from hiatus

You've spoken before about your hardships during the COVID-19 pandemic. Now that you're in the sixth year of your career [and can more easily speak about it], what was the very first obstacle you faced?

The very first stumbling block had to do with OPEN THE DOOR. It was a low period for me — we had already debuted, but hadn't been in front of an audience in two years, and a member (Kinjo Sukai) was also on hiatus at the time. That was right when I was chosen as the center for WANDERING, and the first day of OPEN THE DOOR was scheduled on my birthday. As everything piled up, I ended up putting responsibilty and pressure on myself. I think I was probably like that a lot on tours like OPEN THE DOOR and KIZUNA, where happy and sad things were happening at such a dizzying rate that, even though I could register it all in my head, my heart couldn't keep up at all.

In Japanese, AS ONE means "becoming one". Can you tell us about a moment in your sixth year together when JO1 came together as one?

Most recently, it was our Tokyo Dome show. But when it comes to working together toward a shared goal to produce stages, I'd say it's every tour and every show. It's kind of like the saying, "The more you fight, the closer you become." We sometimes clash as we try to fine-tune things on tour, but that's also when we really get to understand each other. Even now, in our sixth year, I can feel our bond with every new performance we put on together.

Do the members often discuss things with one another?

Quite a lot, I think. We're constantly discussing things. The majority of our setlists for festivals and live shows are basically put together by the members. We always start those off with a discussion, even if it's just two or three songs. We even have little meetings during practice nearly every day.

What position do you frequently take in discussions?

I'm not really the type to voice my opinion. With 11 members, it's likely that we each have different songs we want to do. Even the songs I personally want to perform aren't the songs that suit me best, either. We'd never agree on anything if everyone shared their opinion equally. I prefer it when we reach as much of a consensus as we can, and want to contribute in a way that respects the majority opinion.

But if there's anything I want to perform or showcase, I'll create a song myself to promote like I did this time, making sure to keep my solo work distinct from what I do with JO1. I've stopped worrying or struggling about it ever since I started thinking this way.

Has anyone’s approach to discussions changed over time?

(Kinjo) Sukai was on hiatus at one point. Before that, he was trying to persevere in his own way, but I think that didn't always get through to those around him. I've really felt that he's been earnestly trying to change himself ever since his hiatus. He might even be the member who contributes the most in discussions these days. His change is so clear to me that there's no need to tell him so, but it'd make me happy if he resonates with this article after reading it.

Under pressure at the first live performance with an audience

After more than five years of working together, your relationship with the members must have changed. What do the other members mean to you?

They're my comrades in arms. We've gotten through ups and downs together, and have also overcome live performances together. Many people might say "family", but to me, they're more than that: They're comrades in arms who are also rivals I fight alongside.

Finally, would you please say a message to JAM?

The fans mean everything to me, so I want to do whatever there is that makes them happy. Even with AS ONE, I've been thinking up all sorts of exciting plans before the theme song is announced [note: this interview was conducted before the theme song announcement]. I'm always thinking of ways we can have fun together, so as long as I don't retire, I hope we can keep enjoying our time together, with smiles until the very end. Please continue to support me. And make sure to go see AS ONE in theaters!

Thank you for sharing your valuable insights!