Interface (partially found -MASA Works DESIGN- Vocaloid song; 2011)
-MASA Works DESIGN- or まさ is a popular Vocaloid producer from Japan. He is known for his unique music style, consisting of mostly EDM and Traditional Japanese music, with his most popular song being "The Fox's Wedding". Masa mainly uses Hatsune Miku and/or GUMI for the voicebanks of his songs. However, prior to his first song released under the name Masa, he used to go by the username ell(エルル). Masa only produced 9 songs while he went by the username ell, one of which is titled "Interface" (インターフェース).
Interface is a rock song featuring Hatsune Miku and Kagamine Rin respectively. Little is known about what the song is about, although there might be a possible connection to the other song Masa produced as ell called "Don't Say Goodbye!" and the claim has yet to be somehow verified.
As of September 11th, 2022, the only things that remained were two thumbnails (They have the same image but are of different qualities), one 10-second clip from a daily Vocaloid ranking catalogue from 2011 found by Decent Artist (@Decent_Artist_ on Twitter) and reuploaded by the YouTube channel "Party High in London".
It was believed that Miku and Rin were portrayed as students in the song, although there is no evidence to confirm that claim, but the song most likely talks about murder, judging by the lyrics and illustrations.
Partial Song Lyrics
In the ten-second clip, we get a set of lyrics which translate to the following:
"Gaaaaah! So much fun, so much fun It's time to play!
With a deep seated grudge, I'll make things a mess."
The thumbnail of the Interface upload contains a few recognizable Kanji and kanas, which might possibly piece together to say "I'll slaughter you now" twice.