http://www.youtube.com/watch?v=SLwXEOxs2Xc
Saikano AMV
o.o

I have only read the book, but is it possible it's from the anime?
There already seems to be a comment asking what song it is, you could always wait. ( Or was that you that made the comment).

Best of luck finding out what it is, sorry I wasn't much help, but thanks for linking the song. ( I ended up putting it in my phone since I liked it so much).

Yes yes, I know I make longwinded comments, but that's just me >.<
I should proof read my comments more, but I won't...
So keep in mind I'm filled with typos

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