They’ve been together for ages and one night Bucky asks Steve to marry him and Steve breathes “yes” and smiles, although there’s a deep sadness in his eyes because they would never get wed. But at home where no one can judge them, they refer to each other as husbands and sometimes call each other ‘hubby’.
The sentence “til the end of the line” becomes really important for both of them over the years. And a day before Bucky has to go off to war, he whispers it in Steve’s ear and then reveals the delicate tattoo on his skin: a thin black line around his third finger, like a ring.
And Steve looks up to him and smirks “that’s not a line, that’s a circle. It doesn’t even have an end—” and then he goes wide-eyed and chokes out a broken “oh” and Bucky tells him to stop crying and the day after, Steve gets his own wedding ring.