Unexpected Effects

My friend suggested that I get the Harry Potter books on tape and listen to them while traveling this summer. I did so but didn't become hooked until the 5th book. I immediately ran out and bought the 6th and 7th books (luckily, this was a week after the 7th book was published) and read through them in one day. I was hooked on the series and loved the idea of Snape and Harry together.
On my return home, my flight was delayed and I had forgotten to charge my laptop battery so I could not do any work. I had this fantasy in my head that was dying to come out, so I searched all over the airport for a notebook and wrote this story on the flight home.
It was quite embarrassing writing it on the plane. I was sitting in first class, surrounded by all these powerful businessmen, and I was scribbling Harry Potter porn in a notepad. After I wrote it, I thought of a sequel, but never got around to writing it because I got sucked into NoG.
I've since been informed that this is a very common plot device, but I swear I read no other stories before I read this one. Any similarities are purely coincidence.
This is my second stab at the story. The first was not very well received due to my poor writing skills. I've since become better, although I am still learning!