*sigh* I have been wracking my mind, and I cannot for the life of me remember where I read this fic. It's called "Transfigurations", and it's a Harry/Draco HP fic. I don't remember the author, unfortunately. I do remember that Harry had been teaching at a school in Florida (US), and was called back to Hogwarts for some reason. I can't remember much beyond that.
If anyone can help me, you will have my eternal gratitude. :-)