A/N: Just a oneshot. Heavy, heavy references of slash. Takes place in Sirius's seventh year/Regulus's sixth year.
Comparison
"Why won't you ever take me seriously?" Sirius asked him, sort-of-frowning. It looked more like a five-year-old's pout.
"It isn't that I don't take you seriously, it's that you have no idea what you're talking about Sirius," Regulus said, leaning against the wall that opened into the Slytherin common room.
"I do know what I'm talking about, I'm not pretentious enough to dedicate myself to something I'm ignorant of."
"Yes you are, Sirius, quit being a twat and just leave it," the younger said, he looked annoyed and vaguely uncomfortable.
Sirius would not give up. "Really, Regulus, are you that blind?" he snapped angrily. "He's a sociopath at best," he continued. "You honestly don't see it?"
Regulus reddened a little in his frustration. "No, Sirius, I don't," he said. "Parselmouth," he said to the wall, which swung open to admit him.
On a normal day, Sirius Black would find that the Slytherin common room password to be a goldmine of opportunity, and would allow himself in to punish Snivellus to make himself feel better. Today just wasn't one of those day. Regulus had done something to the equivalent of slamming the door in his face and he wasn't used to his only brother completely disregarding his concern.
It's not that he cared about how the kid turned out, he was easily influenced, as illustrated by their parents. He wasn't going to listen to reason in the face of sixteen years worth of pureblood bigotry. He just didn't care. It was just…
No. He just didn't care.
There was a sort of slow, mocking laugh behind him and he jolted. He turned around and saw a skinny, freckle faced blond boy looking at him with a infuriatingly superior smirk on his face.
"So let me guess, you're standing there trying to justify why you'd even tromp your pretty little self down here to argue a pointless argument with a brother who's in so deep you'll never reach him. And you justify this by telling yourself 'oh well, I don't care, but…' instead of just admitting you care," he said, clapping his hands together and smiling at Sirius in a way that made him look entirely mad.
"Shut up, Crouch."
"Look, despite what you think, you're never going to get through to him. No matter how right you are," Barty Crouch (Jr., as it should be emphasized) said, sighing a little. "I can't waste my time telling you this."
"I will get through to him," Sirius said stubbornly.
"On his deathbed maybe."
"And with you involved that'll only be a couple years. Or would you prefer Azkaban? Maybe you and him could share a cell."
Barty rolled his eyes. "The problem with you is you can't acknowledge that sometimes people don't need to know the truth."
"You're going to hurt my only little brother, why the fuck shouldn't I tell him the truth?" Sirius said, his voice rising.
"I never I'd hurt him. On the contrary. I have no intention of hurting him."
"So you're going to keep him as your precious, special little lapdog forever?"
"Why not? I like it, he likes it. No harm, no foul."
"You're using him."
Barty rolled his eyes. "Look, Sirius, he's nearly a year older than me. However much power I have over him is completely voluntary."
"Fuck you."
"And you resort to petty swears when you've lost. Gryffindor trait? They left that out of the Sorting Hat's song. I can't see why, such an admirable trait."
"You're completely insane."
"Prove it to him."
"If he'd see it for himself-"
Barty cut across. "You trying to make him see my questionable sanity would be like me trying to make you see what an arrogant, bullying git James Potter is. Or what a spineless loser Peter Pettigrew is. It'll never happen."
Sirius saw the logic in that. Not that he'd ever admit it.
"Just let it go. Let Regulus think I'm some kind of saint if that's what he wants to think."
"I can't."
"You refuse to."
"No difference."
"Lots of difference. Can't implies the inability to. Refusal is the ability to but not the desire."
"You're a scumbag."
"But your brother quite likes me. For want of a better word."
"He's in love with you," Sirius said. He felt a little revolted at the idea.
Barty snorted. "You're in love with Lupin, don't give me that look."
"That's different. At least the feeling is mutual."
"I never said it wasn't."
"You never said it was, either," Sirius said. He felt quite accomplished when Barty had no quick retort for that.
"That's completely irrelevant."
Sirius felt like at this point the was pulling ideas out of thin air to win this argument. "Admit it. You couldn't bear to see him with anyone else, even just friends. It's all about you. You're totally selfish."
"Stop describing yourself Sirius, it's not flattering."
Sirius stopped as he opened his mouth to retort. He had no argument for that. He could think of a thousand ways he was nothing like Barty Crouch. But just as many ways that he was.
"Look. You have this horrible animal instinct to protect your sibling, I get it. I don't care, the second you got blasted off that family tree he became completely out of your reach. He became all mine. No more sharing during the summer, no more listening in on your sibling arguments and petty idiocies. He doesn't have to tolerate you anymore, and I won't either. Realize that no matter what you think of me, I'll still be in your brother's life. Because he wantsme there. Your opinion is irrelevant and that's never going to change."
"You'repossessive too?" Sirius said, mocking shock. "Well that just quells my doubts completely, I'll give up all my brotherly rights to you and you can keep him under your thumb and be completely responsible for him. And when you two are the budding little stars of the Death Eater Christmas party, you can be responsible for him then. And when he realizes he's not cut out to be a Death Eater. It'll be your fault. Especially if he dies. The guilt will probably make you a touch crazier than you already are, so be prepared."
Barty sneered a little. "You jump the gun a lot. Regulus won't die."
"Yeah right. He won't last a year as a Death Eater."
"I won't let him die!" Barty said, his voice finally rising.
"The panic is setting in. Here's the problem with you possessive types, you think that having control over a person will save them if need be. You forget to realize that they are capable of making decisions without you and one or more of those potential decisions could be fatal. You can't stop people from dying. It's a human thing."
"I wouldn't let anything bad happen to him."
"Honestly, Barty," Sirius said, turning his back on the younger boy. "You're the worst thing that's ever happened to him."
"Shut up. Just shut up Sirius. You don't even know your brother."
"Well I can't say we were ever as close as you two are."
Barty rolled his eyes. "Do you have to take things disgustingly?"
"I'm just being realistic. I've never, let's say, topped my brother. Or bottomed even. You don't strike me as a bottom. Just one more thing we have in common."
Sirius was satisfied that Barty flushed a little. "You're incorrigible."
"So are you."
"Did you ever think that maybe Regulus likes me so much because I somehow manage to be just like you but without being a blood traitor?" Barty asked, backing towards the door of the common room.
Sirius just left after that comment.
Returning to the common room, he didn't say a word to anyone, just climbed up to his dormitory.
"Sirius?" someone said in a quiet voice.
"Hey Moony," he muttered, flopping into his bed.
"What's wrong with you?"
"Do you think I'm like Barty Crouch Jr.?" he asked immediately.
"Why?"
"Barty said I was. He said that's why Regulus likes him. Or something. But I can't be like him. He's…a sociopath."
"Well you do have things in common."
"Yeah apparently we both prefer topping."
Remus turned bright red. "You're impossible."