You got me hooked from the beginning, and left me hooked until the end.
My only complaints are a couple of sentences that sounded awkward:
Matty and I would pretend to be embarrassed, but she knew we weren’t really, that we just had to say we were.
That definetly just didn't sound right.
Also:
He would place a kiss on my forehead, then creep back out, putting his shoes on in the hall after repeating the process for Matty
Putting the bit about Matty at the end, it was as if you forgot about it so just added it in on the end, just change the sentence order here.
Finally:
Mom would blush, even though she heard it everyday.
This confused me a bit. I think if you said "she heard him say it everyday" I think that would work a lot better(:
My one other problem was the beginning and end. They sort of contradicted each other. In the narrator's head they were perfect. But at the end you say this isn't reality. The end was a tad too poetic, and didn't seem to fit in with the rest of the story.
Apart from that I loved it, vivid, engaging description. You really left me wanting to read much more. I wish it hadn't finished!
