I've received a lot of "I don't understand" reviews about the last chapter so this last and final update with be the explanation.
First of all, the story is done with. It's completely over. The last update was the last and final chapter. Second of all…about the note…
It wasn't a fake note or anything. Ayame had always been jealous of Kagome and she was the one who had always wondered why Kagome never said yes to any of the offers made by any guys. Guess I should have made that a bit more clear in the beginning.
Then it was her who threatened to tell Kagome about the whole 'backpack thrown in the river' ordeal. That part was in chapter 2 (maybe 3?) The last chapter we find out it was Ayame who had thrown the backpack in the river and Kagome knew all along.
The whole note was just another jealousy issue of Ayame's. She was jealous of Kagome for getting together with Inu yasha instead of Kouga. So she wrote a note about them sleeping together but didn't actually know that it had happened. She left it on the school grounds knowing someone who pick it up and read it. Blah blah blah. That's how the rumor started. It was Ayame who started it. Not too creative but, eh, whatever.
Anyway, that's the end. As I said, even I'm kinda disappointed with the end. Maybe I'll go back and change the whole chapter. Nothing really worked out how I wanted it too in the end. Hmm, I'll keep that in mind. So thanks for reading! Hope this clears it up a little more!