"Ai no Melody/Chōwa Oto (With Reflection)" (愛のメロディー／調和oto 〜with reflection〜, Melody of Love/Harmony, Sound (With Reflection)) is Kokia's 15th single, released on January 1, 2006, a month before her greatest hits collection Pearl: The Best Collection. The songs were used as the ending and opening theme songs for the animated film Origin: Spirits of the Past. "Chōwa Oto (With Reflection)" is a re-recording of her song "Chōwa Oto" from her Gai Records' management era album Trip Trip (2002).

The song is a piano-backed ballad. The song begins piano-backed, and leads into a chorus backed with percussion, guitar, piano and strings. The majority of the verses have a minimal arrangement, mostly only piano with occasional strings and other sound effects.

The soundtrack version has the same arrangement as the original, however has embellished background music in part (such as added harp) and extended instrumental sections.

The lyrics express the love for another, likening them to "sunbeams filtering through leaves," and saying that they had given the song's protagonist hope. The person feels that "Because I have you, I'm able to be like myself." Therefore, she sings a song born of the love they have for that person.

The song is sung in a 12 note scale. The song begins with a 1:50 introduction in three steps: first Kokia sings Japanese lyrics against background sound effects and the piano. This leads into a section with added percussion where Kokia counts numbers in English. The final part of the introduction features Kokia harmonising with herself without lyrics.

This leads into the chorus, sung in coded Japanese. The chorus' arrangement is backed with a more complex variety of instruments. This leads into a more pop-inspired bridge, backed with added sound effects. This then leads into the chorus twice more, and finally one single abridged chorus backed only with piano.

There are three sections to the song's lyrics: standard Japanese, numbers and coded Japanese. The numbers are a code that represents the letters of the Latin alphabet (1=A, 26=Z). When decoded, the numbers (3 25 15 21 23 and 1) wrote the song's name in wāpuro rōmaji (C Y O U W A). The coded Japanese section features reversed syllables (such as the lyric "nimiunooto denzush," when reversed gives "Oto no umi ni shizunde" (音の海に沈んで, sinking in a sea of sound)). Both the standard Japanese and coded section have lyrics which bring up many natural images (such as a "sea of sound," "drop of water," "quiet forest," etc.).

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Wikipedia