Nature's Changing Course (слэш)

Snape wakes up expecting to celebrate his seventeenth birthday. Instead he finds out he's missed the last twenty years and the wizarding world is celebrating the death of the Dark Lord.
Cast adrift in this strange world, where he is seen as both hero and villain for things he has no recollection of, he struggles to come to terms with suddenly being famous and the unlikely attentions of one Harry Potter.