“Children's World” is a vocaloid song by Utsu-P, released on November 14, 2010, as part of the TRAUMATIC album. It features Kagamine Rin and Hatsune Miku on vocals.

The lyrics deal with disillusionment with the current state of the world, how youth see that they can improve the world using their new worldview. the end of the song implies that they had only really seen a narrow, childish view of the world from the start anyways. There's also a hint of chuunibyou in the lyrics as well.

The song is 3 minutes, 52 seconds long. It has a comparatively upbeat feeling compared to the rest of the songs from TRAUMATIC. Starting from it's bouncy main riff, to it's verse section with alternating lead and rhythm guitar tracks. The advancing verse section and pre chorus have a more conventional metalcore baseline to round out the song. The chorus of the song features backing vocals and a “sing song” style to it especially compared to other tracks from this album. When the verse returns, it features a more dynamic lead guitar and a more playful vocal melody sung by Hatsune Miku. The lead up into the breakdown is a bass solo, while the breakdown itself accents the screamed vocal line using pinch harmonics. The song ends with one last repeat of the chorus and main riff.

A re-recorded version was featured on the album Post-Traumatic Stress Disorder in 2016.

(Color coded to Hatsune Miku's solo line)

この愛なんて無くてさ　荒みきった中学生
毎日が戦争で　闘争の日々続く
黒焦げの社会を　牛乳瓶越しに見て
本当の答えなど　見えるはずないってさ

足りない頭には　飲めないコーヒー入れた
等身大の兵士　から笑うレイシスト
ありったけの刃抱えて　ほら

僕たちはありのまま　泣き笑い感情表現していた
「絶望は空想」と現実感無いまま永遠を追いかけてた

立ち入っちゃいけない場所で　良い子達が秘密の集会
森羅万象全て繕って　大人たちを欺いてやるぜ
月並みな表現で言うと　それは仮面という奴なのか
錆び付いた箒を凶器に　僕らが世界を変えてやるのさ

空想と妄想を　繰り返し黙ったまま
等身大の僕ら　から笑うオトナ
ありったけの刃抱えて　今

少年はちっぽけな　アイデンティティ振りかざし戦う
その刹那見えたのは　初めての絶望と現実、セカイ

ああ　ああ　ああ　僕たちが
ああ　ああ　ああ　見ていた
ああ　ああ　ああ　セカイは
ああ　ああ　ああ　ゆりかごだった

僕たちはなすがまま　泣き笑い感情表現していた
体温に包まれた　それは大きな小さな籠の中

(Color coded to Hatsune Miku's solo line)

Kono ai nante nakute sa susamikitta chuugakusei
Mainichi ga sensou de tousou no hibi tsudzuku
Kurokoge no shakai wo gyuunyuubin-goshi ni mite
Hontou no kotae nado mieru hazu naitte sa

Tarinai atama ni wa nomenai koohii ireta
Toushindai no heishi kara warau reishisuto
Arittake no yaiba kakaete hora

Boku-tachi wa ari no mama nakiwarai kanjou hyougen shite ita
“Zetsubou wa kuusou” to genjitsukannai mama eien wo oikaketeta

Tachi-iccha ikenai basho de yoi ko-tachi ga himitsu no shuukai
Shinrabanshou subete tsukurotte otona-tachi wo azamuite yaru ze
Tsukinami na hyougen de iu to sore wa kamen to iu yatsu na no ka
Sabitsuita houki wo kyouki ni bokura ga sekai wo kaete yaru no sa

Kuusou to mousou wo kurikaeshi damatta mama
Toushindai no bokura kara warau otona
Arittake no yaiba kakaete ima

Shounen wa chippoke na aidentiti furikazashi tatakau
Sono setsuna mieta no wa hajimete no zetsubou to genjitsu, sekai

Aa aa aa boku-tachi ga
Aa aa aa mite ita
Aa aa aa sekai wa
Aa aa aa yurikago datta

Boku-tachi wa nasuga mama nakiwarai kanjou hyougen shite ita
Taion ni tsutsumareta sore wa ookina chiisana kago no naka

(Color coded to Hatsune Miku's solo line)

“There's no such thing as love” So says the unrefined middle schooler
War wages every day, The fight continues every day
While we're watching the charred black world from our milk bottle
They said they couldn't see the real answers anyways

The undrinkable coffee was poured in that dim-witted head
While the racists were laughing at our life-sized soldiers
With all we have, we hold this blade in our hands, look.

We are what we are, Laughing while crying and showing emotion
「Despair is a fantasy」 without a sense of reality, we were just chasing that for eternity

The good kids secretly meet up in a place they shouldn't go to
I'm going to fix everything and trick the adults
We express ourselves with trite sayings, isn't that like someone wearing a mask?
The rusted broom is my dangerous weapon, and our world is rapidly changing

I repeat my fantasies and delusions while remaining silent
Our life-sized us, the laughing adults
With all we have, we hold this blade in our hands, now.

The boy is tiny, yet he'll brandish his identity in the midst of war
In that moment I saw the despair and hard reality of the world for the first time

Ah, Ah, Ah, We are all just
Ah, Ah, Ah, watching
Ah, Ah, Ah, the world from
Ah, Ah, Ah, our cradles

We're at eachother's mercy, Laughing while crying and showing emotion
Enveloped in eachother's body heat inside of a big little cage

• The Post-Traumatic Stress Disorder remake version neglects the final chorus' first line of lyrics, instead just repeating the first chorus' first line of lyrics

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