サンドリヨン (Cendrillon)

サンドリヨン(Sandoriyon "Cendrillon") is a duet originally sung by Kaito and Miku Hatsune composed by Signal-P (music) and Orange (lyrics). The original video was illustrated by Yunomi-P and the Title Logo was provided by Sacrow.

The title's song: Cendrillon is a French word which means 'Cinderella' and as the name suggest it, its story basically is a retelling of Cinderella with a dark twist.
 * Nicovideo Broadcast
 * Youtube Broadcast

Background
A girl (Miku) attends a ball to kill the prince (Kaito) when the clock strikes twelve, since she was handled by the fairy godmother. As the girl and the prince meet, they dance together and fall in love. The girl becomes increasingly conflicted as midnight approaches, falling into a dilemma as she does not want to kill him. Eventually the girl stabs the prince when the bell rings. The final lines of the song discuss the moment right after the prince is stabbed while she can still feel him with her, and muses on how they want the moment to last forever.

The PV is very ambiguous and can be alternatively interpreted as Miku having a split personality, and the "darker" side stabbing Kaito while the "good" side cannot stop it.

This, added to the open of the lyrics and the popularity of the song, had generated numerous PVs with different interpretations.

English Lyrics
English translation: Cendrillon

アドレサンス (Adolescence)
A lyric arrangement of Orange, it could be considered another version of Cendrillon, but due that the new theme is unrelated to the original song is considered as a different song.

This song is about the growing-up Rin and Len, as fraternal twins they were like two peas in a pod until they grew up to come to the age of puberty where they can't share the same bed as they did when they were little children. They no longer are perfect look-alikes since they hit adolescence and their bodies are developing differently. They both sing about how hard it is to be separated because they are always together. While Rin states throughout the song that she doesn't want Len to leave her, he remains hesitant throughout the song until the end when he states that he will no longer retreat from her.

This song is quite popular among the Kagamine's fans and has several PVs and interpretations and views. One of them is that as they grow up and their gender differences became evident they began to feel physical attraction between them, conflicting with their fraternal feelings. Various PV has touched the subject in different degree.

Hiro Tamura also published a doujinshi called Perdu that shows the story and background behind this song.