I believe those are the lyrics for AKINO – Sousei no Aquarion. I love the song but I've never seen the show, so I don't know how this relates to the image, or the show... or anything.
Those are the lyrics to the theme from "Genesis of Aquarion." I'm not really familiar with the show, so I don't know why they phrased it that way, but basically it's just a fancy way of saying "I've loved you these past 12,000 years." I'd guess kind of like saying "four score and seven years" just to mean "87 years."
Ok, I figured that was what was meant, but didn't know if there might have been more to it. The fact that it is song lyrics makes more sense for there to be a strange construction anyway. I've changed it to the more sensible translation.
Shinjidude: it's better English to use a timespan with past perfect. It's 前から in Japanese, but that doesn't translate to "since" in English in this context.
piespy: It's tame in comparison to Yuki in post #81147, so I'm not sure that this is full blown yandere. Her facial expression would beg to differ though. I'm not sure.
葉月: Thanks for the fix-up. I had meant "since" in the same meaning as yours, as in "from then until now and continuing". As usual though, I like your translation better than mine.
The lyrics Yuki is reciting represent the feelings that the show's primary antagonist, Touma, has for the angel Apollonius, who is reincarnated as the main character Apollo.
