Identifying a song

Hiya!

I was watching a documentary and heard a snippet of a song which I immediately fell in love with.

It's a rock song, sung by a male (most probably). I couldn't figure out much of the lyrics because the narrator was talking over it. I tried searching it online with what I figured out to no avail.

Oh well, here is the lyrics that I could figure out. I'm still not good at Japanese so sorry, I'm sure I must have made a mistake or two.

(???)...ことまなくかすんでゆく.

猶予うの心あなた ???（couldn't hear the last part, sorry）
闇を切り裂きはじひゆく
楽しい人の心かなたえと...

If anyone would be willing to take a look, it starts at 07:18 in the following video.

http://www.youtube.com/watch?v=bX3aK2naa-A

Thanks a lot beforehand!

That song is sung by the girl who is a eating disorder that documentary taked up.
It seems that her name is 吉田優賀里(Yoshida Yukari).
I found another her song on Youtube.
http://www.youtube.com/watch?v=qhg7a8SCtcE