The Classic Anime Song-like OP of “Nageki no Bourei wa Intai Shitai” – An Interview Commemorating the Release of Kiyono Yasuno’s “Algorithm”

A Classic Anime Song Vibe: ‘Nageki no Bourei wa Intai Shitai’ OP – Kiyono Yasuno “Algorithm” Release Commemorative Interview

From the magazine “Megami Magazine,” which features artists who sing anime and game theme songs, comes the interview series “Megami’s Voice.” The January 2026 issue features Yasuno Kiyono, who has released her new single Algorithm.

A New Frontier Number as an Artist

――The title track “Algorithm” is the opening theme for the second cour of the TV anime ‘Nageki no Bourei wa Intai Shitai’ (which can be translated as ‘The Lamenting Ghost Wants to Retire’). It’s a number that gives off a strong, powerful feeling.

It’s a song where the band performance shines, very typical of an anime song, right? When I first received the song, I thought, “Is it really okay for me to sing this?” because it had such a different flavor from the songs I’ve sung before. Precisely because of that, it was also a song where I struggled to figure out what kind of vocal performance was being asked of me.

――At what stage did you decide on the direction for your vocals?

I built the image during the key check while consulting with the music producer, Masao Fukuda. Actually, initially, the phrases in parentheses within the lyrics were also scheduled to be sung by me as the main melody. But the breathing was difficult, and when I tried hard to sing it, I couldn’t achieve the powerful vocals required by the track, so they became backing vocals. In the end, I think positively that the call-and-response style that resulted actually increased the rock-like feel. Also, I think it’s good because it becomes a point where everyone can sing along at live performances and such.

――The key is somewhat low, isn’t it?

To express a powerfulness with my voice quality that wouldn’t be overpowered by the song, we thought a slightly heavier key might be better, so we lowered the key by about three notes from the original pitch. When singing high notes powerfully, I often focus my consciousness at the crown of my head, but doing that inevitably distances the voice from its source in the abdomen, which requires delicacy. However, this time, since the key was set lower, it felt easier to aim and hit the target.

――As a song, it’s not just purely bright, but what kind of expression were you aiming for with your tone of voice?

I sang with the intention of imbuing it with prayers and wishes. This song seems to convey something simple, yet it carries the contradiction that everything about it is a facade. It expresses an idealized, cool version of oneself, so while singing it properly, I hoped the contradictory feelings underlying it would surface.

――The protagonist of ‘Nageki no Bourei wa Intai Shitai,’ Klai, is exactly carrying such feelings.

This is my own interpretation, but I imagined the protagonist of this song as having built up a perfect illusion, singing loudly and powerfully about “the self I want to be.” But, seeping through from behind that, is the reality that it’s not truly so. As the singer, I also aimed to put up a brave front, perform this story, and sing through it.

――In the anime, the OP plays while the story is progressing, right?

Since the first cour, the way it leads into the OP has been very stylish, hasn’t it? Sometimes dialogue comes in while the song is playing, and I felt they were aiming for a point where the work and the music blend together. No two OPs are the same, so I’m also looking forward to seeing in what form it will play in the future.

――The TV size version has a piano intro added that’s not in the full version.

Actually, the piano was a phrase added after my recording was finished. You can only hear it in the anime, so I hope you’ll enjoy it.

――What do you think is the charm unique to the full-size version?

It’s that it never loses its sense of speed until the very end and has no weak points. The right phrases come in exactly where you want them, and I feel it’s a beautifully constructed number on an almost geometric level from start to finish. This time, YOURNESS was in charge of the performance, and on the band recording day, everyone was gathered. Of course, they went into the booth one by one, but I felt a family-like warmth, and my heart fluttered in that sparkling atmosphere, thinking, “So this is the air of a band.” And it created a good kind of tension, the feeling that I too am becoming a part of these creators and will sing.

Memories from the Music Video Shoot

――The first press limited edition includes a Blu-ray with the music video for “Algorithm.” Please tell us about your memories from the shoot.

The song recording was around last winter, and the MV shoot was this summer. The director of photography, also inspired by the song’s sense of speed, envisioned refreshing footage, so there were many location shoots—and first of all, it was very hot (laughs). In the overall composition, there’s me in white clothes running through the city day and night, and another me in black clothes who actually wants to run away, carrying something weak. It’s imagery of the “light” me who wants to be strong and the “dark” me who wants to hide and withdraw meeting, merging, and dancing powerfully. This time, since I was playing two clearly divided personas of light and dark, we thought it would be better for not just the costumes but also the expressions to be distinctly different. So, I consciously aimed for a strong, cheerful look in the white outfit, and when in the black outfit, to show hesitation and rarely smile. However, I tend to smile if I let my guard down, and even in the white outfit, the director gave me direction like “Be more powerful,” so I focused on properly acting out my own duality.

About the Coupling Track and the Single as a Whole

――The coupling song “Re:fresh” was first released digitally in March 2024.

I was in charge of the lyrics, and listening now, I fondly remember being unsure about which phrases to use. But I polished them quite a bit, so I feel I worked hard on it, and I also have the impression that this song solidified one form of my lyric-writing style. When I heard the song composed by Tomoya Kawasaki, scenes immediately came to mind due to its dramatic nature. Based on that image, I feel I was able to deliver the messages and feelings I wanted to sing in sync with the music, with high purity. I think it’s a straightforward, energetic, classic-type song that’s very “me,” so if you listen to it simply without overthinking, you might receive at least one dose of mental vitamins.

――This single contains two songs with such different tastes. What are your thoughts on how the single turned out?

In a way, I think it became a miraculous single. “Algorithm” is close to the outwardly adult-like, leader-behaving side of Klai-san, while “Re:fresh” is a song that says, “Even though tough things happen, let’s take off the persona (mask) for a moment, laugh with the world and people you love,” fully affirming one’s likes. It also feels like it expresses the carefree part of Klai-san that thinks, “I want to be lazy, I just want to do fun things.” This is completely coincidental, but I feel it became a great-value single that manages to express both the front and back sides of Klai-san.

Voicing in ‘Nageki no Bourei wa Intai Shitai’

――You also voice the character Altovaran in ‘Nageki no Bourei wa Intai Shitai.’ What kind of character is he?

Altovaran has a cool visual, but he’s a character whose pace gets disrupted by Klai-san. I think Klai-san’s easygoing nature stands out even more through his interactions with Altovaran, so please pay attention to that. Also, I actually also voiced the Onsen Dragon that appeared in episode 19. It’s basically not dialogue but cries/voices, and the director asked me to express the OP theme melody with those cries (laughs). I expressed it with cries starting from the piano melody part in the intro, so I hope you’ll see how it was actually used in the footage.

――Finally, please give a message to the readers.

As a Kiyono Yasuno single, this has become a new frontier for me. “Algorithm” is, in a good way, a different type of song from my previous work, but I think it will resonate with many of you who love anime songs. For me personally, since I haven’t sung classic, quintessential anime songs before, it was a new challenge. I feel it’s become a song that’s fun to listen to even at festivals and live shows, where you can feel good shouting call-and-responses. As someone singing this type of song, I have the mindset of a newcomer, so if you get a chance to hear it at a venue somewhere, I’d be happy if you could throw your energy back to support the song. I believe it’s a song that is completed with all of you there, so please listen to it a lot and sing along with me!

Profile

Yasuno Kiyono / Born July 9th. From Miyagi Prefecture. Affiliated with Avex Pictures.
Began solo artist activities in 2017 with the mini-album Namida. Has since released 4 singles, 1 album, and 4 mini-albums.

Information

‘Yasuno Kiyono 5th LIVE Tour 2025 ~Bokura no, Ame ga, Yamu made.~’ is currently being held.
For details on ticket purchases, check the official website: https://avex.jp/kiyono-yasuno/

“Algorithm”
Now on Sale
DIVE II entertainment

• First Press Limited Edition: 2,800 yen (tax incl.)
• Regular Edition, Limited Anime Edition: 1,650 yen each (tax incl.)

The title song is the second cour OP theme for the TV anime ‘Nageki no Bourei wa Intai Shitai.’ It’s an intense rock tune composed and arranged by Shohei Koga, a member of the rock band YOURNESS. The coupling includes the first CD release of “Re:fresh,” which was previously released digitally in March 2024.

— Megami Magazine Editorial Department

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