Lost in Waiting by laceymcbain. This is one of my favorite stories just to sit inside of and enjoy. I think a lot of that has to do with the past she builds for John. It's logical and thorough and very clear, and it makes the virgin premise logical, which is hard with that kind of idea.
Better Than by seiyaharris. It's a cute John the MD AU, and it's just--really nice. Though I'd give a lot for an expanded version of this one. Cause the premise alone is awesome.