I just want to say that this story was amazing. You managed to create such a tense atmosphere throughout and your characterisation of Voldemort is spot on. I really like Vincent's realization that he is not going to leave alive.
This story reminds me a lot of The Portrait of Dorian Gray by Oscar Wilde. It has the same self-obsessed subject as well as the idea that a portrait can capture not only the soul of the subject but the soul of the painter as well. I love the ending of this story, especially the last line.
My only criticism is that you could maybe lose the eights. It kind of looks like a row of ants marching across the page and interferes with the mood of the story.