I didn't have it in myself to go with grace, and so the battleships will sink beneath the waves.
“Leaving, brother? Without even so much as a goodbye?” Sirius turns to see Regulus perched on the stairs of Grimmauld Place. There was a reason Sirius didn't say his farewells. Neither brother had any discernible expression on their face, nothing that any stranger could ever pick up on. Regulus' brow was furrowed, only just, an expression of despair, of disappointment. Sirius' mouth was set in a thin line. Regulus knew that this was his resignation, shame even, in leaving this place and not even extending a hand to his little brother. Regulus knows why Sirius chooses to leave quietly. You cannot blame a ghost for haunting a house in the opposite way to which it once lived there.
You had to kill me, but it killed you just the same.
Regulus stands, he chooses to do this face to face. "Goodbye." Sirius' voice is rough around the edges. His skin is sallow in the candle light, hair limp and tangled. He looks like a Black. He looks like every Black that ever had their face burned off of the tapestry. Maybe this is their curse, not the actions of the leaver but the suffering of the one left behind. “It was always my life for yours.” Regulus' voice is cool, collected. He will not acknowledge his brother's inner tempest, simply because it isn't his. “So naive brother. This is not her letting you go. This is her telling you, never come back. This is her telling you, I knew I’d have to have a second son.”
Cursing my name, wishing I stayed, you turned into your worst fears.
Regulus sees Sirius shudder. He cannot falter, he must play his part. Everything in their lives is an orchestra. Regulus was no better than a puppet, but this act of the play matters. “I paid for your freedom, Sirius Black." Regulus' voice was almost melodic, mocking. Sirius stares directly into his brothers eyes. He tries to understand this parable but he cannot reconcile his brother into the role of both the punisher and the punished. He turns and his footsteps echo down the corridor. To Regulus, the slam of the door sounds almost like the snap of marionette strings. The deed is done. The demon is free of the body that once controlled it.
And you're tossing out blame, drunk on this pain, crossing out the good years.
Sirius would always be Regulus’ first and last word. It echoes around the cave like salvation. Sirius. Saved. Sirius. Saved. Sirius. Saved. Regulus knows their eyes are identical. Regulus knows he will die. Sirius will always carry a part of his brother, and Regulus will die with a part of his. Regulus finds only relief in the knowledge that he would be free from his punishment. He thinks it to be natural, this yearning to be his brother's other half again. Regulus hopes Sirius can understand him, that one day he'll revere him as an oblation. He hopes he is his brother's favorite sacrificial lamb.
And you're cursing my name, wishing I stayed. Look at how my tears ricochet.
The Daily Prophet arrives at Sirius Black's window like it does every day. Remus is making breakfast. This isn't routine and this isn't normal. It's 1979 and the first time in months neither he nor Remus were doing something for the Order. The normalcy, the domesticity almost puts him on edge. He skips to the best part of the Prophet - Obituaries. He's always had a morbid obsession with betting on which Black would go next. He sees his brother. He reads his name. He watches Regulus blink up at him from the portrait with the exact same eyes Sirius thanks him with.