Hell I found the song! It was this one:
www.youtube.com/watch?v=ypQHev9XAD4

Slut's Symphony, dont know if you said it was this one before.

yeah same song odd wording though because it translates to female pig symphony

Ahhh I see thats why we couldnt find it. And when that little girl was singing it sounded faster compared to the one on the video.

she sings this part
www.youtube.com/watch?feature=player_detailpage&v=RkZc2c8gdEE#t=167s
"you take it from the bottom half"

or "all i need is the crotch" cant remember 100%

I think its the 2nd one...and I gotta rewatch it now...damn.

No no no, I meant a song alike 'Satsugai' the one you mentioned was a bit 'slow' where as the little girl was singing fast and saying 'rape her cunt'.

if i remember right though she says " you take it from the bottom half" which is a lyric in the female pig symphony, damn wish i could remember what episode it was so i could find out