Prima is an interesting vocaloid. She is Zero-G's equivalent to Crypton Future Media's Miku Hatsune. Keep in mind both company's are 3rd party's. The full out owner of vocaloid is Yamaha. If that helps clear up any confusion.
You can read more about her here
http://vocaloid.wikia.com/wiki/Prima
Seance Prima is not as famous as Miku I think a sample video might help. Here is a youtube link. http://www.youtube.com/watch?v=ZEls-dG3lFk
