A/N: I don't own Harry Potter and make no claim to, but i thought I would write this, if you like it when you've read it and can be bothered don't be afraid to review!
Roma
Regulus sat looking at his fingernails, he supposed that he should begin to man up, he was going to join the Dark Lord. He was about to be initiated, he was about to receive the Dark Mark on his forearm. He was about to say that yes he could torture others, knowing that he would never again, could never again be considered innocent. His parents might carry through with the pure-blood mania that Lord Voldemort preached, but recently he had fallen out of love with it.
His brother might not know it, but in Hogwarts, Regulus would always watch Sirius carry on with his friends. He watched Sirius appear to the rest of the world as the happy pureblood, that guy who wasn't against whoring around, that guy who went against his parents and hell most of the rest of his family's belief system but Regulus knew better. He liked to think that Sirius missed Regulus, missed him at least, missed his little brother.
After all, Regulus missed his big brother. He missed the guy who would willingly climb trees with him. He missed the guy who always seemed to find the sunny part on a dark day. He missed his big brother, the guy he could climb into bed with after a nightmare. Sirius had always taken the punishment from his parents, the disappointment, the lectures, the shame of having a pureblood son who really didn't give a damn about blood purity, or the rest of it. Sirius had always taken the punishment, the constant Crucios, all to protect his little, baby brother.
Regulus wanted his relationship with his older brother to go back to the way it had been before Hogwarts. They had been best friends, you never found one without the other. Regulus could remember writing tons of letters to Sirius, telling him about life at home. But Sirius never replied, in the few letters that Sirius had sent home, he had talked about James Potter constantly, about Remus Lupin and Peter Pettigrew constantly. Regulus had felt left behind, when the letter telling them Sirius had gotten into Gryffindor.
For the first few weeks, before he realised that he had been forgotten by his bigger brother, before he realised that he had been kicked to the kerb, he seriously considered asking to be put in Gryffindor. Regulus was sleeping in his big brothers bed when he had a nightmare, it comforted him to know that his big brother was still there. He wanted the old relationship he had with Sirius back. He eventually realised that his brother didn't really want him anymore. That was fine, but Regulus still wanted Sirius. He was considering Ravenclaw, after all they were smart, and could still be considered ambitious, would that disappoint his parents so much?
In fact, he remembered the summer when Sirius came back from his first year, he told Regulus all about Hogwarts, the secret passages, what classes were like. But he kept going on Potter and his merry band of friends. Regulus had then realised that he didn't mean much to his brother, after all he never mentioned any of the letters, never asked Regulus what it was like all those months at home. It all kicked in when on the Express train ride, Regulus was forgotten about in favour of Potter, he realised that the Status Quo had changed, he wasn't in it anymore. He doubted that his brother noticed when he left them to go find an empty compartment. He certainly noticed that when his cousins Narcissa and Bellatrix asked him what was wrong.
When the Sorting Hat said that he had the brains to go into either Ravenclaw or the sheer ambition to go into Slytherin. Strangely it also hinted that Sirius had enough of that latent bravery laying deep within his soul to go into Gryffindor. He thought of his brother and thinking that his brother wanted nothing more to do with him. He thought of how hard life could become on him, if he had chose to move away from the family house of Slytherin, how disappointed his parents would be of him. To spite his big brother, he picked Slytherin. After all, he supposed, if the git was ready to cut off all ties with him, why shouldn't Regulus be prepared to live his own life? Having said that, Regulus has looked into his brothers eyes after the Sorting Hat had called out its decision, he seen the disappointment. To him, that was like being punched in the stomach.
He quickly realised that week following when his brother followed him that Sirius was disappointed and no longer saw himself as what he had earlier affectionately called Reggie's older brother. He wouldn't be there anymore to protect his younger brother. Unfortunately Regulus could not bring himself to call Sirius names or blackmail him at first, family might not mean a lot for Sirius but it sure as hell did for Regulus, but when he noticed that this small amount of information was getting picked up by the older members of Slytherin House. The members that saw nothing wrong in dropping a few hints in Walberga and Orion Black's ears, he stopped seeking out Sirius and when he did come into contact to his older brother, when they had an audience of the Snake household, he insulted his brother. It tore him up inside, but it had to be done.
By the time Regulus had reached his third year, he cut the emotional strings from his heart that lead to Sirius, he could no longer see any form of affection coming from his older brother. He avoided Sirius like the plague, if he saw him coming at him in a corridor, he would turn and walk in the other direction, he didn't want Sirius to see that he was slowly dying on the inside. Because he knew that if he was to look at Sirius, directly in the eyes, then his big brother would surely see the kind of pain that Regulus was regularly going through. He didn't want to give Sirius the satisfaction of knowing that he, Sirius was getting to Regulus.
It was slowly getting worse at home as well, with his parents resigned to believing that they had lost their elder son. Sirius might not believe it but they had pinned their hope on him, after all the older brother was supposed to go out and blaze a path, with the younger brother following meekly behind. When Sirius had left, it had made their parents tougher on Regulus, he had guessed with the increased scrutiny that came from other Slytherins, that his parents were regarding Regulus more closely. Making sure that he didn't fall off the proverbial bandwagon and befriend muggle borns. In his parents views, a half blood was tainted, you couldn't trust a half-blood not to stab you in the back one day, if they were talented then by all means 'collect' them.
Punishment was also getting harsher, Regulus couldn't be anything other than the perfect son, he had to clean up Sirius' mess. It meant small torture curses, thankfully not Crucio, but it was bad enough if he stepped a foot out of line. He had to learn Occlumency and practice it to a greater degree than before. If he slipped up, Regulus wasn't sure what would happen.
When Sirius had ran out of the house following the big argument the summer before Regulus' fifth year. Regulus could distinctly remember peeking round the door, feeling so disappointed that his older brother was leaving. He swore that Sirius saw him, heck Sirius even offered to take and shelter him at the Potter Manor, but Regulus had felt that might push his parents even further over the edge. That night when everybody else had gone to bed, he secretly locked Sirius' room, now only Sirius or Regulus could get in there. But Regulus didn't want to go in there, for that meant accepting that his brother was truly gone. He deeply considered that night that maybe the Sorting Hat had got it all wrong, his brother couldn't be brave if he walked out on his family, if he had walked out on his brother. Maybe Gryffindors weren't as brave as they liked to make out.
Regulus had desperately looked forward to September, he needed some private time to decide where his loyalties lay, heck that was what he was telling himself but in reality he just wanted to make sure his brother okay. If Regulus ever got so much as a whisper that the Potters' weren't treating his big brother right, he would go crazy on their asses. He still cared deeply for his brother, maybe not as much as before but he could even now clearly recall the good times with his brother. When they were growing up, when they had been the others friend, only friend.
That all changed though when Sirius barely looked or acknowledged Regulus at school, if it had seemed bad earlier in his school career, it was truly bad now. Sirius seemed to hold nothing but contempt for his brother, at least in a public arena. Even if Sirius had denied the Black family name, he couldn't stop hiding his feelings. It seemed to sink in when Regulus realised that he could no longer read his big brother so successfully, at all really. It drove a spike further into Regulus' already rapidly tortured soul.
He had tried to forget all about Sirius until his graduation, and to an extent he did, however he still found himself getting tortured when something brilliant happened to him and he had no one to tell he quickly realised. He went out of his to avoid his brother, learning the hiding spots in the castle, becoming a faster runner.
When he was in his seventh year and he started becoming truly infatuated with the Dark Arts. The Dark Lord learnt of Regulus and his older ties, really he blamed Bellatrix, she shouldn't have told him anything. The Dark Lord blackmailed Regulus telling him his family were as good as dead if he didn't join. While he didn't particularly care for Walberga or Orion - they had chased out Sirius, he couldn't stand if there was some way of prolonging Sirius' life beyond this war. He did the unspeakable and joined, just to keep Sirius safe.
He only hoped that someday Sirius would recognise this.