There’s something quietly devastating about choosing ずうっといっしょ！ (Zuutto Issho!) as your birthday cover song. Kadou Mikaru (蝸堂みかる) did exactly that, uploading her take on Tatsuya Kitani‘s bittersweet track on June 1, 2026 — her own birthday — with the simple caption: “Let’s stay connected.” If that doesn’t tell you everything about where this cover lives emotionally, the song itself will.
The Original: A Love Song With Teeth
ずうっといっしょ！ is one of Tatsuya Kitani‘s most emotionally complex songs, originally released featuring CeVIO AI vocalist Kasane Teto. Its English subtitle is “ALWAYS BE WITH YOU XD” — and that ironic XD tells you everything. The lyrics open with borrowed chargers and missed last trains, two people wearing each other down while vowing to stay connected, calling it a war of attrition they’re choosing to enter together.
It isn’t a sweet love song. It’s a song about the kind of bond that’s already calcified into something painful — where staying together feels less like a choice and more like a ring that won’t come off. The narrator tells the other person she’ll stay with them as their life’s greatest regret, flashing back to the relationship over and over, realising bitterly that she was cuter when they were still together. And yet — through all of it — the refrain keeps coming back: zuutto issho. Always together. Even in matching nightmares.
Choosing this song for a birthday is a statement. Mikaru knew exactly what she was doing.
The Sound: Tender, Restrained, and Genuinely Moving
What Mikaru brings to this cover is a softness that reframes the song’s darker edges without defanging them. Where the original leans into a sharper, more ironic vocal delivery, Mikaru’s version is warmer — almost gentle — which somehow makes the lyrics land harder. There’s no distance between her and the words. She sings them like she means them.
Instrumental arrangement by Karafac gives the cover a clean, stripped-back feel that suits Mikaru’s voice perfectly. Nothing clutters the vocal, and every emotional beat in the melody gets the space it needs to breathe. Ashitaka‘s mix keeps things intimate — this is a headphones song, the kind that sounds like it’s being sung directly to you in a quiet room at the end of a long day.
The result is a cover that feels less like a performance and more like a confession. Whether that was intentional or just the natural result of her genuine affinity for the material doesn’t matter — it works either way.
A Cover That Suits Her Perfectly
Kadou Mikaru debuted on August 15, 2025 as the guitarist of the Nijisanji girls band unit “今宵、××と夢を見る。” (Yoi Yume), alongside Yagyu Shino on bass, Togawa Nonoha on drums, and Nekoyashiki Miku on keyboard. Her persona is that of a 777-year-old snail who just wants to live life freely at her own pace — easygoing on the surface, but quietly sensitive to the emotions and actions of those around her.
That sensitivity is exactly what you hear in this cover. Zuutto Issho! is a song about emotional entanglement — about bonds that hurt and endure anyway — and Mikaru sings it with the kind of quiet understanding that only comes from actually feeling what the words mean. Her fanbase, the かたつむり組 (Katatsumuri-gumi), will hear this and understand immediately why she chose it.
Illustration by スイミン and video direction by 有栖 永真 (Alice Eishin) round the package out with visuals that carry the same gentle, slightly melancholic warmth as the vocal. The art doesn’t scream birthday celebration — it breathes the same quiet feeling as the song itself.
A Birthday Song That Leaves a Mark
Most birthday covers are celebratory. This one is something closer to intimate — a gift from Mikaru to her listeners that also happens to be deeply personal. The fact that she released it on her own birthday, with a caption about staying connected, turns the whole thing into something that feels genuinely meaningful rather than just a content drop.
ずうっといっしょ！ is a song about never really letting go, even when things are complicated and painful and beautiful all at once. Coming from a VTuber who describes herself as a snail just trying to live peacefully while being deeply affected by the people around her, it’s a choice that makes complete sense. And it lands beautifully.
Track Credits
- Title: ずうっといっしょ！(Zuutto Issho! / Always Be With You XD)
- Original by: Tatsuya Kitani (キタニタツヤ) feat. Kasane Teto
- Cover Vocal: Kadou Mikaru (蝸堂みかる)
- Instrumental: Karafac
- Mix: Ashitaka (アシタカ)
- Illustration: スイミン
- Video: 有栖 永真 (Alice Eishin)
- Released: June 1, 2026
- Channel: 蝸堂みかる / Kadou Mikaru【にじさんじ】
▶ Watch: Kadou Mikaru — ずうっといっしょ！(Cover) on YouTube
