"A Method of Annullment" by
Snegorochka-lee First read: 21-02-2008.
Notes: The thing about a Pensieve is that it can both mask and reveal, depending on the time of day. Memory is always a tricky one, after all: look too closely and you'll start to doubt what you see. 6500 words only but so intense... In this Marauder Era story Snape's pensieve gets played with by Sirius and James... or not. But it ends up full of memories of him and Lupin fucking like bunnies all over the place. Snape, who only allows himself to fantasize with Lupin with tremendous guilt and of course would never put anything like that in his Pensieve. Snape watches the "memories" fascinated until he can't no longer stand it and he confronts Lupin about it. Lupin is first horrified but soon they are watching the memories together every night... You can figure out how it goes from there.
I loved Remus, who's logically aggressive towards Snape and not at all like his adult self (finally someone seems to see that someone like adult Remus wouldn't have fit all that well into the troublemaking Marauders and that his adult self is a grown up version, someone created after the lose of his friends and only family and a terrible war). And Snape as well, who's resentful, in denial and helpless in his need to be strong.