When Remus is 11 years old, he finally learns what it means to have friends. He learns that to have friends means having someone to share his time with, someone to help him with his homework and someone he can offer his own aid in return to, someone to have whispered conversations with after the sun has set and he’s supposed to be asleep, someone who sneaks into his bed to punch his shoulder and ask him what he’s been up to today. Even when the dormitories have long since fallen silent and he can’t see anything in the compact darkness of his bed, he can feel Sirius’ smile a mere few inches from his own.
When Remus is 14 years old, he learns what it means to fall in love. He learns that to be in love means that every time he sees Sirius, his stomach flutters, that his mood brightens every time Sirius gives him attention, that his skin burns every time Sirius touches him, that the last thing he thinks about before falling asleep at night is Sirius’ smile. He doesn’t know what he’s supposed to do about his feelings and for the time being, it doesn’t bother him. He’s happy to love Sirius from a metaphorical distance, because after all, Sirius smiles more at Remus than at anyone else.
When Remus is 15 years old, he learns what it means to have his heart broken. He learns that to have his heart broken means watching Sirius parade around the hallways, hand in hand with his new girlfriend, watching them share an armchair in the common room every evening, watching them share kisses before and during classes. He refuses to acknowledge the hollow feeling in his chest and when James asks him what’s going on, he gives an noncommittal sound in response. Sirius still smiles at Remus more often than not, but not as often as he smiles at his girlfriend.
When Remus is 16 years old, he learns what it means to have his heart mended. He learns that to have his heart mended means wanting to burst from happiness, wanting to touch Sirius all the time, wanting to tell McGonagall go do something unmentionable to herself when she tells Sirius to go sit somewhere that isn’t next to Remus. They spend what feels like hours every evening in Sirius’ bed, kissing and touching and having mumbling conversations about everything they’re gonna do together once they’re done with school. Sirius smiles happily when Remus tells him, blushing, that he doesn’t much care what he does as long as he’s doing it with Sirius.
When Remus is 21 years old, he re-learns what it means to have his heart broken. He learns that to have a broken heart can come from having two of your best friends brutally murdered, from finding out the reason they were murdered was that their best friend, Remus’ boyfriend, betrayed them, from coming home to an empty flat where everything from the large clock on the wall to the very ceiling whisper about memories of happier times. Remus sits on the couch every evening, staring out into open air. Once in a while, his eyes stray to the photo of himself and Sirius sitting on the book shelf. Sirius is smiling at the Remus in the picture, and the Remus that’s sitting on the couch doesn’t bother fighting the tears, for once in his life.
When Remus is 34 years old, he learns what it means to have his will to live being reignited. He learns that to have his will to live being reignited means being filled with heat from top to bottom, being something that resembles happy, being able to think to himself that maybe, just maybe, there’s a chance he won’t grow old alone. When Sirius has to flee, Remus doesn’t get the chance to say goodbye, but he doesn’t miss the way Sirius smiles at him for a fleeting moment in the Shrieking Shack.
When Remus is 36 years old, he learns what it means to watch the love of his life be ripped away permanently. He learns that to watch the love of his life be ripped away permanently means having his insides turn to stone, having every last trace of hope in his chest vanish, having the vague sense of happiness that’s been building up inside him over the last two years be cruelly torn out by the roots. He watches as the curse hits Sirius in the chest and makes him stumble backwards, hears Harry’s screams and on pure instinct rushes forward to hold him back.
Sirius smiles at Remus as he disappears.
It’ll be the first and last time Remus doesn’t smile back at Sirius.