It started sometime after Sirius fridge broke down. It was fine until one day it just wasn’t, and as on cue James and Lily moved out, leaving Sirius alone with a broken fridge. And then there was the engagement, making James and Lily busy with wedding plans and grown up stuff that Sirius just wasn’t all that ready for. So he went to Remus’.
Remus’ flat was small and made even smaller with Remus’ books and teacups littering every inch of it. He worked a lot, or not at all, and his fridge worked perfectly. So one day when Sirius came home from the grocery store with a six pack but realized he had nowhere to keep them, he apparated to Remus’ to put his six pack there instead.
“I put beer in the fridge” Sirius said through a mouthful of cereal (Remus always bought the kind in funny colors that left your teeth covered with sugar) as Remus came in through the door that evening after work.
“Alright. Can I have one?” Remus asked as he took of his coat, dusted with snow.
“Yeah. What’s for tea?”
Sirius stayed for four days the first time, before apparating back to shower and change clothes. Two days later he was back, and this time he stayed a whole week. In the beginning he slept on Remus’ couch, but the old thing was awfully uncomfortable and after waking up with back pains he decidedly snuck into Remus’ bed at night, lying close to the sleeping werewolf and waking up all tangled in Remus’ arms. Sirius just shrugged and snuggled closer into Remus’ worn t-shirt (which he suspects was originally Peter’s) and taking advantage in his friend's’ heat.
They don’t talk about it really, Sirius doesn’t see what the big deal is, and it keeps happening. They wake up in each other’s arms, eat breakfast together (which usually is yesterdays take-out and tea) before they both go to work and spend their days apart only to come together at the end of the day, eat together (cereal, candy or take-out), watch movies or play video games before going to sleep, Sirius curled up in Remus’ arms with his head under Remus’ chin. It becomes routine, and soon Sirius’ clothes are in Remus’ washer, his books and movies and records are stern about in Remus’ flat and he’s not been to his own place for two months.
And then one morning Sirius wakes up to find Remus right there, like always. The sun is shining through his tousled curls, and Sirius notices for the first time the red and grey flecks in Remus’ hair. He can’t help but smile. He can’t help but reach out and count the curls as they twist around his fingers, his chest filling with warmth at the soft crunch emitting from his nails and the hairs making contact. When he looks down again, Remus is awake, staring at him with searching eyes.
“Hi” Remus whispers, since there’s only breath between them.
“I like this” Sirius says, a small smile on his lips.
“No- or well, yeah, but I mean this. Waking up with you”
And that day they just stay all day in bed, Remus’ stubble tickling Sirius skin as they kiss, and Sirius tung tastes like stale cigarettes and sugar.