おｋ、緑は、敵だ。 (Ok, Midori wa, Teki da.)

Background
"OK, Midori wa, Teki da." is an original rock song featuring Kagamine Rin and the derivative Akita Neru. This song is unusual in that the voice used for Akita Neru is based off of Kagamine Rin's voice rather than Hatsune Miku's. The original Nico Nico Douga upload has been deleted.

The story of the song revolves around Rin and Neru's jealousy of the popularity of Miku.