Words I thought I'd choke on, figure out
As much as Sirius would hang shit and tease Regulus, they were brothers. And he would do -well has done for that matter- anything and everything to keep him safe. It took him years before agreeing to even let Regulus keep going home after James found out what their home life was like and practically forced Sirius to go home with him. Sirius knew realistically that Regulus was safer with their parents than he was, but it still didn't mean Sirius trusted them.
That was the thing with his parents that took him the longest to accept. no matter how nice they were he should always be expecting the other shoe to drop. from his mum taking him out to lunch, just spending time with him, but something as simple as he couldn't stand still while she spoke with a friend would end up with him muttering healing spells in the darkness of his room. it wasn't so bad as he was younger but when he was sorted into Gryffindor it was like all bets were off. she evolved from just hitting and throwing things at him, to hexing and cursing him.
When Regulus brought up talking with James again while they were waiting to leave Hogwarts, Sirius knew that it was Regulus was trying to protect him from what is to come with returning home. but-Sirius lied, he lied, and he told Regulus that James had said he needed time-that James didn't want him to come over. Which he knows isn't fair because he hadn't said more than a few words to James at all let alone asking to come over.
He knew his lie was going to fall through and bite him in the ass eventually. He just didn't think that it would come full force when he was trying to get off the Hogwarts express. He stood by one of the large pillars waiting for Regulus to get the last of his things off the train, when he spotted James, Peter and Remus. James was searching the crowd for someone-Sirius deep down knew it was him, He knew it didn't matter what James thought of him-he was too good a person to actively send Sirius back to his parents. And of course, just as Regulus got off the train, he locked eyes with James. Quickly grabbing his and some of Regulus’s things he left, not looking back at them. Missing the hurt look on James's face as he watched the two Black brothers leave. And Sirius could only hope that Regulus hadn't noticed.
~~~
The two of them were transported back to Grimmauld Place. The ride was silent only the quiet sounds of Sirius’ foot bouncing on the floor from his nervous leg bouncing. Regulus didn't mention it, even though Sirius knew that it was a big pet peeve of his brothers. He guesses Regulus was just as anxious for Sirius’ return. He hadn't exactly left home on good terms with anyone, he had just sort of declared he was going to either stay at Hogwarts or go to the potters during the holidays. He had even tried to convince regulus to come with him, but the younger Black simply shook his head and told him ‘Someone's got to keep this place running.’
Once they actually got to those large doors Sirius felt small again, like he was 13 years old terrified of his parents knowing just what they were capable of. He almost wanted to turn around, go to the potters, beg for forgiveness, but he couldn't do that to Regulus. Not again. So instead, he bit his tongue and followed after Regulus. And for the first time since he left the house was quiet, there was no yelling-no cursing. It was-oddly comforting. Trailing behind Regulus he stopped at his room reaching for his doorknob, before Regulus stopped him “don't-” he said his hand knocking Sirius’ off the doorknob. “Mum-she you know what Shes like-she” Regulus hesitated “she didn't take you leaving well” he continued. “We can clean it up later-just not now” he said his eyes flicking to his own room “come on-you can sleep in here tonight” he said motioning for Sirius to keep walking.
~~~
Sirius hesitated, wanting to open his door-see the damage done to his room, but-he didn't instead he just walked towards Regulus’ door pushing it open gently. Sure, he had been in his brother's room before but never like this, he had been in there to annoy him-comfort him after copping the brunt of his mother's anger. But never-never because he didn't have anything else. While Regulus got some spare sheets and pillows set up for Sirius he began talking again.
“Mum and dad-they don't know that you're here and you and I both know they won't be happy about it, so just-you know keep your mouth shut” he said standing up-brushing off his pants turning towards his older brother and for a moment-Regulus froze. He had seen Sirius with some real injuries, he had seen his brother bloodied and beaten but-looking at his brother now? He doesn't think he could be angrier. Sure, Regulus had his doubts about James telling Sirius that he couldn't go to the potters, but the idea that all of Sirius’ so-called friends had made him feel like he had to come home. The one place where Sirius actually got out of? That filled Regulus with a rage he couldn't really explain.
Sirius was sitting on the bed his head tilted slightly looking towards the picture on Regulus’ bedside table. A picture of the two of them and their cousins when they were younger, they were all smiling for once. It was rare honestly. But while Sirius was occupied Regulus had the chance to look over his brother, he could see the toll on him, the way his hands were still shaking like he was cold, the way he had curled himself into something small and out of the way. He didn't know what to do-and that, that hurt more that Regulus was expecting it too.
Sirius had spent his whole life convincing Regulus things would be okay, he would come into Regulus’ room and comfort him while still bleeding because that's what brothers did. But Regulus didn't know what to do-he didn't know how to fix this. How to help. So, he simply sat next to Sirius looking at the picture as well “It'll be okay” he said. Not leaving any room for arguments.
~~~
It had already been relatively late when they had gotten back. So, Sirius wasn't surprised when only a few hours later, Regulus was asleep in his bed curled up on his side-facing the door like he had done since he was young. But as for Sirius? he doesn't know how long he laid there for. He thinks it was at least another hour after Regulus had fallen asleep, but he couldn't be sure. And by that point he couldn't take it-he just had to know what had happened to his room why Regulus was so keen on not letting Sirius inside. He had even brought it up before Regulus had gone to bed but to no avail. So, throwing back the covers Regulus had let him borrow. he was up, grabbing his wand holding it between his teeth as he left the room, once he was in the hallway he slowly took the wand into his hand, uttering ‘Lumos’ watching for a moment as the dark hallway lit up around him, he slowly walked towards his own room and inhaled shakily as his hand went to the doorknob again.
He froze for a moment-God could he really do this? He didn't have much time to think about it before he was pushing the door open, holding his wand out gently as he looked around.
He couldn't see much around him with the only light being from the tip of his wand. so he walked into the room, closing the door behind him and flipped the light on. "Nox" he spoke-his words trailing off slightly as he really looked around his room. from what he could see standing at the door was chaos. all of his things were destroyed and burned to a crisp.
God Regulus thought they could fix this? He walked over towards the bed and took in the large, scorched marks that dipped deep enough to show the wooden bed frame was rotting and black. His walls were ruined-the same thing, thick black scorch marks over anything in the room that remotely made it his. His bedside table was knocked over-anything left in his closet had been thrown on the floor or burned-he didn't think any of it was salvageable. He never thought he would be back here-and sure he knew his mother wouldn't take it well. But this-this was a whole new level.
Standing in the middle of the room, Sirius regretted walking in-he regretted not listening to Regulus. he regretted not asking James if he could come home. but then everything just started coming up-the shame he felt for putting Severus in that situation, putting Remus in a position like that. and it was overwhelming. he felt like he couldn't breathe. as his back hit the door behind him he felt himself sliding down the splintering wood. his legs curling under him-or giving out. he honestly couldn't tell which one happened first. tears were rolling down his face and he couldn't stop them. his hand was covering his mouth in an attempt to muffle his cries but-he couldn't stop them.
He was ruined-he felt it all the way down to his core. he had done this to himself. he had no one to blame but himself. but as his mind started to ease there was only one thing on his mind-repeating over and over again.
no one would want him now would they?