Inspired by @danceinthunder 's post
It had taken him so long to break through Regulus's walls, he'd hardly taken real time to think about what would happen after.
He had been so obsessed, so enamored, so taken by even the slightly prickly exteriors of Regulus's masks, that he'd not even thought about what was underneath.
Well, that wasn't true. He was obsessed with what was underneath.
Occasionally, he'd caught a glimpse. When he shot him a compliment across the hall, a small, sweet, sincere smile cracked through the permanent scowl for half a second, and James celebrated. When James finally got the chance to pull Regulus into his arms, even for a second, he swore he heard the other boy let out the tiniest sigh of contentment, and it rang through James's ears like the sweetest melody for weeks.
But when he finally convinced Regulus that they were worth it, that Regulus himself was worth it, and that their feelings for each other were real and not some sort of joke or prank or something that was going to be ripped away at any second, James just expected Regulus to still be...well, indifferent. Aloof. Difficult to read. He wasn't mad about it- he loved working to gain one of Regulus's rare smiles. But he didn't expect anything to change.
But the day after they'd fought for an hour, snogged for two, and then declared themselves boyfriends, James almost fell out of his overstuffed armchair in the Gryffindor Common Room when Regulus walked towards him, grabbed his arm, and folded himself underneath it, tucked neatly into James's lap like they did this all the time.
"R-Reg?" James asked, lips tickling dark tresses as Regulus's face pressed lightly into his neck. He took a deep breath, inhaling the scent of mint, ink, and old books, and tried not to move, similarly to how he acted when Marlene McKinnon's cat made a home on his chest. "What-?"
"Hi, sunshine," Regulus hummed, his hands snaking around James's hammering chest.
"H-hi, baby," James stuttered, a huge smile breaking out on his lips.
"Whipped," he heard Sirius cough from behind him.
He wasn't going to move until Regulus did.