Firefly: Simon/Jayne
This story broke me. I was in tears by the end. It’s amazing, my favorite story in the fandom by far but utterly, completely heartbreaking in that way where you know what’s going to happen and it’s inevitable but you just know that it should happen that way and that it wouldn’t be right with any other ending. Such a satisfying and emotional read. Jayne is so sympathetic in this and Simon is heartbreakingly rational.