Song List

1. "Daughter of Evil", the first song of the series, was released on April 6, 2008. It uses the voice of Kagamine Rin and details the basic story of a cruel princess (Rin) ruling in a corrupt manner, using her servant (Len) to order the fall of the green kingdom after the man she loves is found to be in love with a woman from there, and subsequently "being executed".
2. "Servant of Evil", the second song of the series, released on April 29, 2008. It mainly uses the voice of Kagamine Len, though a small portion near the end of the song includes Rin's voice. It details the story of how the twins were separated when they were very small and how the only thing of Rin Len could ever see was her soft, kind side, and of how he killed Miku (after falling in love with her) and eventually traded places with Rin to be executed. Before dying, he wishes they could be reborn as twins again.
3. "Regret Message", the third of the series to be released (uploaded May 25, 2008), tells of Rin's feelings directly after "Servant of Evil", related to the plot story which Akuno-P posted on his blog. Rin realizes that it had been her own selfishness that had killed her brother, and the wish she made was apparently also the Servant's wish before he died. At the end, the Princess and the Servant are reunited as Kagamine Rin and Kagamine Len.
4. "Daughter of White", the fourth song of the series, released on January 6, 2010. The official English title of the song by Akuno-P is "Bystander".^[26] Unlike the previous songs sung by Rin and Len, this is sung by Yowane Haku, detailing the events of the series from the viewpoint of a new character, which had never been mentioned before in the previous songs. It is the longest song in the series, and also details some events after the end of "Regret Message" (Haku trying to kill Rin but eventually feeling pity for her).
5. "Twilight Prank" was originally composed by mothy for the Theater Play event. It was performed by Shimoda Asami. The song shows a small snapshot of the princess and servant's lives as small children, avoiding a mysterious "demon" in the twilight. The demon says he is hungry, and the two, having buried a chest in the sea, are running from him. The two decide to "split" day and night between each other, Rin being "day" and Len being "night". Len eventually realizes the demon will be always hungry no matter what and decides to share his snack with the demon. In return, the demon tells Len a secret about the ocean (likely the legend of the glass bottle). Len promises to later share this secret with Rin. Though he has already released its cover with Rin and Len on his "EVILS FOREST" album, he uploaded it on Nicovideo on August 3, 2010. The official English title of the song by Akuno-P is "Day and night".^[26] He commented, on his blog, that he purposefully changed the spelling of "Twilight" to "Twiright" in the video he uploaded. Also he explained he did that because "right" means "correct" and "normal", "twi" carries the meaning of "twist", the ones who are performing it are "R"in and "L"en, and the prince gave a sweet to a "demon" while the princess did not in the song.^[27] 

Related song

• Re_birthday [ぜんまい仕掛けの子守唄3]/ Re_birthday [Zenmai-Jikake no Komoriuta3 (Clockwork Lullaby3)]
  • "Re_birthday" is the third song in the "Zenmai-Jikake no Komoriuta " series. It was released on Dec 27, 2008.
  • Akuno-P on his blog stated that this song was made for "Regret Message" in "Daughter of Evil" series and is the answer to it. He purposefully made the both titles start in "re" because of that. Its title involves three meanings, the first one is "birthday" to celebrate Len's released date, the second is "reincarnation and revival", and the third is the "response to (Re)gret Message". Also he mentioned there are some hints that show the relation with "Regret Message" in the original video of "Re_birthday".^[28] If you playback the original video of "Re_birthday" frame-by-frame at 3:31, you can find frames that give the hints. One of them the inverted word "リグレットメッセージ" appears, and another one has "もしも生まれ変われるならば", which are the words from "Regret Messeage", at the upper left.
  • In this song, Len is alone in a dark room not being able to see, then he hears a voice and starts to remember the evil that he has done. Then his arms are in red handcuffs (representing blood shed) and his ankles are in blue chains (representing the tears spilt). Suddenly Len hears a melody of someone's voice coming from somewhere (the melody of Zenmai-Jikake no Komoriuta sung by Rin). He is forgiven his actions in the past, given a new birthday and reborn.
  • Key words which Akuno-P gave to this song is 「黒い部屋　巨大なぜんまい　僕はひとり」/深い闇の中の出来事。あるいは誰かのみた夢。/真実はどこかの光の中　("A black room, a huge clockwork, I am alone"/ An event in the deep darkness. Or a dream which someone saw/ The truth is in the light at somewhere).
  • Though "Regret Message" has not been officially taken in the any of the series for a long time as the author has not confirmed it, a lot of fans have initially believed it is in the "Daughter of Evil" series. They also often regarded "Re_birthday" as a part of the Story of Evil. Also in the original video of the song has some clues that seem to imply the relation. Later, a song "Daughter of White" and a promo of the novel "Daughter of Evil, Cloiture of Yellow" show the connection of "Regret Message" with the series.
  • However, Akuno-P has not yet confirmed anything about "Re_birthday" and the song is still officially in the series of "Zenmai-Jikake no Komoriuta" . Although this topic is still open to debate, many fans think "Re_birthday" is about Len's experience after his death in "Daughter of evil" series, being tortured by a "ghastly voice" and being trapped in a room while remembering his memories over and over again.

Re-releases

There has been a number of new releases of the songs. One of them is the ACT2 version of the first two songs, which supposedly features an improved version of the Kagamine Rin and Len VOCALOID2 program (however, mothy believes these mixes to be inferior).
Another version includes the "velvet mixes" of "Daughter of Evil", which were released on December 27, 2009, in celebration of Rin and Len's birthday. The two songs feature artwork from artists put together by mothy, which confirm certain elements in the plot. A "velvet mix" of "Regret Message" was released on mothy's album "prelude to forest".
38 keywords are hidden in the original videos of "Daughter of Evil ~velvet mix~". Also the same number of lines are shown in that of "Servant of Evil ~velvet mix~". Each keyword and line can be a pair and if they are put together, there will be 38 dialogues of characters in the story, including characters who do not appear in the songs of the series. Those can be clue to interpret the story of "Daughter of Evil" series deeper.
Some examples (note that they are not in chronological order in the story): keywords hidden in Daughter of Evil ~velvet mix~ / "a line hidden in Servant of Evil~velvet mix~"

• Power struggle among the Lieges / "One successor is enough"
• Pure-hearted Assassin / "The children have no sins..."
• Wim of a Sorceress / "No man can be any good"
• Death of a Queen / "Knight the Lion, please take care of the child"
• Mighty famine strikes / "All the people would die if this goes on!"
• Childish conspiracy / "I'm pissed off! He really makes me pissed off!"
• Commander of Royal Guard who has the name of Lion / "Why...you..."
• Deadbody at the riverside / "No one can disobey her now"
• Girl in a red clothes / "No! Father! Father!"
• Wish of one-thousand-year Tree / "I want someone to be my friend"
• Maiden of Tree / "Who, are you?"
• Green Purge / "Kill all the women with green hair!"
• Loose-tongued Maid / "I heard it, I heard it♪"
• Survived Heresy / "Why, why!?"
• Lament of a King / "Revenge... revenge!"