Oh, this was truly amazing. I love your future wizarding world, its integration with Muggles and the little details that make it all so very real. The history and the politics of different parts of Europe are fascinating also, and turn your story into such a wonderful, rich tapestry of a world that is recognisable as Harry Potter, but quite culturally different and so wonderfully original.
Your Viktor is marvellous - you fill him in with a rich personal history that makes his current attitude and vocation perfect for him. I abolutely love his seriousness coupled with his guilty glee at the trappings of wealth that he tries so hard not to overindulge in.
And Snape! Yay! Of course, his personality comes through right from the first few letters - though I did wonder, for a little while, if they were a red herring. His understated loneliness and gradual warming to Viktor's company was a joy to read - there are some parallels there to meeting a fellow fan online and gradually coming to know each other that I really enjoyed.
And may I also give three cheers for Magda? What an absolutely awesome original character. She totally needs her own fic series *g*