Mystery Author, thank you! You've created such a carefully-crafted, intricately detailed and fully realised world within this fic and it's beautiful.
First of all, having this take place in the afterlife is A Magnificent Idea. Not only do we get canon compliance but it's the perfect place to unpack Snape. It's safe; after all, he's already dead and nothing worse can happen to him and it's the perfect setting, at Spinner's End where it all started, for him to come to terms with himself.
What a fantastic character study of Snape and Lupin this is! Snape's calendar keeping and his determination to produce a rationality of his afterlife; the broken railing on the stair that reveals so much within a single phrase; his meticulous record-keeping and his realisation that he has no one to share his research results with reveals so much of him. That deep-seated need for public recognition in combination with his lifetime's distrust of other's opinions is one of the marvellous contradictions of his character. I really appreciate that this isn't overwritten; that you trust the reader to go with Snape as he comes back to his research.
I love the slow unpacking and exploration of Snape's sexuality; the freedom that he can find with Lupin to do that. That budding awareness and long build-up is just so hot; Snape can't wank often enough for me. :D Fabulously hot sex that's made all the better for waiting!
Do you know, though, it's that theme, that we are self-creating and that we do that within a physical and social environment, that I think will stay with me most. This fic is a wonderful illustration of Snape and Lupin learning to rebuild who they are, exploring themselves and each other and creating a greater-than-the-sum-of-its-part moreness together.
Secret Santa, I couldn't be more grateful. I'm going to treasure this fic, and I'll be reading it again and again until I'm familiar with every nuance and beat within it. Thank you.