You have an interesting start here. I'd love to see you expand it and write more.
You do need to get a beta reader, however. While the story idea is a good one, you could use some help with the pacing of a story. And a good deal of help with grammar, spelling and punctuation. Chapter 2 was only 12 sentences long. That really needs to be broken up. And edited for readability. Poor spelling and grammar turn a lot of readers off of a story, and even professional authors have editors. It's not a failing to get a beta/editor; it's an important step in producing a professional quality piece. The failure is in NOT trying to get one.
Personally, I am interested in seeing where this will go. You've already got my two favorite pairings already: HP/GW & HP/GD. The two of them together is awesome.
Thanks for taking the time to write for us. We appreciate your efforts.