WELL LIKE. IT'S A VOCALOID SONG I LIKE. AND. I THINK I KNOW WHAT IT MEANS AND FRANKLY, I AM JUST PUTTING IT HERE SO I DON'T FORGET. .3.
SO HERE TIS:
They cut out both of Miku's eyes (Len flashbacks to the "donor" picture when he sees her) so Len and Rin each get one blueish-green eye and Miku gets their yellow. When they (Rin&Len) look for the exit, Rin pointed him in the direction of a door that said "Rin and Len the Disposal Place," so he assumes she wants him dead/disposed of. Len runs off. Scientist want ask Rin where Len is. Rin tells them but then realizes that they want him dead. She goes mad and kills them all. When she is poised over Len with the butcher-knife, she is actually about to cut out his eye (thus she says "look at me"), and replaces it with her other blueish-green eye. They then switch clothes and hairstyles before other scientists come, so Rin is actually the one being "disposed of". "We may have switched bodies, but you'll always remain a nobody" refers to how he must keep the change a secret and always operate under the name of "Rin Kagamine" - because, technically, Len Kagamine is dead. That is why, at the end, it says Congratulations "Rin". That is also why throughout the song, it always says "The bodies will be exchanged".
/END HELLA LONG INTERPRETATION/
And the vid is here if you would like to watch: