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OtapediaAi Kotoba (song by Hatsune Miku)

“Ai Kotoba” (愛言葉), known by its official English title as "Love Password" was released on July 21, 2009, and was composed by DECO*27. One of his most popular works, it is about Hatsune Miku expressing all of her feelings toward a special someone who has always taken care of her.


Since October 2008, DECO*27 had used the voice synthesis software Hatsune Miku to create songs and post them to Nico Nico Douga. In July 2009, he wrote this song so that it was geared towards listeners who were avidly following his music. It is a cute pop song where DECO*27 uses such phrases like "I like you, I love you". In a 2010 interview, DECO*27 stated that he wanted to create a song that conveyed what Miku meant to him, and what she means to her fans. He continues that this song was the most memorable song that he had created.
On the Nico Nico Douga page for the song, DECO*27 displays the lyrics of the song in the form of a letter that drew positive remarks from fans, noting that having it appear in this way complements the song itself.
The song was included in DECO*27's debut album, "Love Theory" which was released in 2010. It is also included in the "VOCALOID Super BEST -memories" album which is a collection of popular Vocaloid songs that was released in 2013. In addition, the song was added to the SEGA-produced video game series Hatsune Miku -Project DIVA- (console). It is featured in Hatsune Miku -Project DIVA- 2nd (2010), and Hatsune Miku -Project DIVA- Arcade (February 24, 2011). It is also available for Sega's iOS game Miku Flick released on March 9, 2012.

The song has two sequels also produced by DECO*27.

On October 8, 2013, to celebrate his 5th anniversary of uploading songs to Nico Nico Douga, DECO*27 created "Love Password II". He created the song while believing he had more to say that he didn't place in the original "Love Password", and felt like using "II" instead of "2" was a better way to label his sequel song. In December 2013, DECO*27's best album "DECO*27 VOCALOID COLLECTION 2008~2012", "Love Password II" was included, though it was released in 2013. This album begins with "Love Password" and concludes with "Love Password II".

On October 8, 2018, DECO*27 published "Love Password III" to YouTube where it has since gained over 5.5 million views and an overall 95% like-dislike ratio. The song was featured in his sixth album, "Android Girl" and has been covered by over 30 amateur singers and around 10 professional singers. The general consensus among fans it that out of the three "Love Passwords", the original is still their favorite as the music and lyrics are very sweet and touching.

The original "Love Password” has amassed 2.2 million on Nico Nico Douga, allowing it to enter the Hall of Legend. This landmark cemented DECO*27's position as one of Hatsune Miku's most prolific producers.

Song Information

  • DECO*27 (music, lyrics)
  • Hatsune Miku (vocals)
  • Jyenyaon (illustration)


Published by Sony Music Publishing C Division under JASRAC
JASRAC Works Code: 164-8314-6

Kanji Romaji Translation
いつも僕の子供がお世話になっているようで itsumo boku no kodomo ga osewa ni natte iru you de My child seem to always be in your care
聴いてくれたあなた方に感謝、感謝。 kiite kureta anata kata ni kansha, kansha. So you have my thanks, my thanks for always listening to her


The song contains the gratitude of the creator for the fans who listen to his songs, and at the same time, Miku’s gratitude and love to those who listen to her. She assumes in the future people may have forgotten or grown out of her, but would be happy just to be remembered, for them to still hold a song dear and think of it nostalgically.

Miku sings about the past that she has shared with her listeners and she wants to continue sharing memories with them. Even during times when the two aren't having strong conversations, she is still thankful for the memories that she holds close to her heart.


[Hatsune Miku] Ai Kotoba (Love Words) [Original Song] - Niconico Video
Love Password - Wikipedia

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