No idea what a five times fic is, and seems the deadline is over, but anyway, here are my thoughts on this piece.

Using the songs is a cool idea of course, and it'll appeal to any music lover (or casual listener even) but it does have some downsides, like
1) it dates the piece because once the songs aren't on the top ten anymore, the likelihood of somebody knowing about them becomes less. Here you have lyrics from the songs, which helps those unfamiliar with the original pieces to understand where you're coming from, but... that brings us to no. 2
2) you gotta take care with the copyright cause the original artist might not like their work being used this way, it's a big IF but a possibility nonetheless

Apart from that, I think this is a lovely, sweet piece, and very modern to boot.

This was very cute. There were a few minor inatances where punctuation was incorrect (mostly just ending a sentance when a comma would be better), but nothing glaring.

I like how you used the numbers to signify how many times she sang, and then the 1 for a duet.

The only thing that threw me at all, was at the end where Tory says "Thank you for being my Nate Ruess", wasn't sure if a word was missing, or if she literally meant, *her* Nate etc.

*Squeals* THIS WAS SO SWEET! :D :D :D *Deep breath* Okay, I'm calm now. Sorry about that. XD Seriously though, even as a romance-hater, I couldn't help but wriggle happily over this. It was just so cute. _
I have to say, I am so thoroughly jealous of Tory. I love singing, but unless my voice is really warmed up, I sound dreadful. :/ I wish I could steal her voice. :(
I also have to say that The Parting Glass is one of my favorite songs, and that The High Kings just totally blow the Celtic Women out the water. XD I've never heard the Assassin's Creed version, but I'm willing to bet THK blow that out the water too. (Major High Kings fan here - couldn't tell that, right? XD)
Anyway. I loved the story, it was just so sweet. _

In the fifth scene, there's a 0 before romantic, right at the beginning of it.

But other than that, it was perfectly adorable! And I just kept imagining you and your girlfriend (though I've never seen her) in the story!