A/N: For the beautiful, amazing, lovely, and absolutely perfect Paula. I love you, dearest. Enjoy!

one: we sin as devils do

I.

He stands in your doorway, bag packed and resting against his hip. Your heart sinks at the sight of him.

Sirius is running away. Sirius is leaving home, leaving you.

"Please," you whisper.

Pain flickers across his face. Maybe he's still not sure. Maybe there's still a part of him that wants to stay with you.

You latch on.

"Sirius," you say, your voice stronger now as you climb to your feet and cross your room.

He tries to look away, but you won't let him. You place your palms against both of his cheeks, forcing his gaze onto yours. "Stay with me," you say, grazing your thumb over his lips.

"Regulus..."

He can't leave. Not now. Not you.

You press your lips to his, trying to ignore the tears falling from your eyes and mixing with the kiss. "Don't leave me."

He pulls back, stroking your cheek. He will stay. However bad things may be for him, he knows that you're worth it. A victorious smile spreads across your face, but it fades when he speaks again.

"I'm sorry."

And then he's gone.

You slam your door, throwing yourself onto your bed and hating your traitor of a brother.

II.

You pace the length of your room, waiting for the door to open. Sirius will come back with a hundred apologies ready on his lips. He'll fall into you, and maybe you'll forgive him.

But the door doesn't open. No one else has entered your room in two weeks and four days.

"Bastard," you hiss under your breath.

III.

Bellatrix smiles a shark-tooth smile when you tell her you're ready. "Always knew you wouldn't disappoint me, little cousin," she laughs, her fingers wrapping around your wrist.

"What happens now?" you ask.

"Now, you burn."

Your fear must show because she smirks and tightens her grip. "Don't tell me you're scared, Reggie," she taunts in mock baby voice. "Having cold feet already?"

You close your eyes. Scared? Yes. But you can't admit to it. Besides, the spite you feel towards your brother is enough to overshadow it. "Hardly," you answer dryly, opening your eyes once again. "I can't wait."

IV.

Your eyes widen with fascination as you examine the skull and serpent on your flesh. It's still there, still real.

A smile twists your lips as you let your sleeve drop to conceal it once again.

V.

Sirius grabs you by the shoulder, steering you into an empty classroom. You try to act nonchalant, resting your weight on your left foot and folding your arms over your chest, but your heart is pounding like mad inside your chest. "Well, this is cozy," you say, trying to exaggerate the boredom in your tone. "Missed me and thought I might fancy a quick shag?"

There's no humor in his face. You can't remember ever seeing him look so grim.

"Why so serious, Sirius?"

"A little birdy told me you have been spending a lot of time with Bellatrix lately," he says, stepping closer.

You start to answer, but you snap your jaw shut, eyes narrowing. Why should you say anything? He's the one who walked away from you, and you owe him nothing.

"Tell me you aren't really that stupid, Reg."

"Tell you? I'll tell you it's none of your damn business what I do anymore. You gave up your right to know," you snap.

He reaches for your arm, and you pull away. Realization twists his face into a mask of agony. "You didn't."

You clench your jaw until pain shoots through the side of your face.

"Regulus, tell me you didn't."

You grab your sleeve and pull, revealing your Mark. "I did."

He pulls you close, his touch gentle now. "It's not too late. You're still young. Dumbledore can help."

You laugh a bitter, dry laugh. "But it is too late," you say, pulling out of those arms you once called your haven. "It was too late the moment you left home."

part two: we love as angels do

I.

When you see the Crouch boy, you assume he's a new plaything for Bellatrix to torture. He doesn't belong there. His father wants to destroy the lot of you.

But Bellatrix squeezes his shoulder, wearing the same dark pride she'd worn when you'd come to her, and you understand. Except you don't.

"Crouch? Really?"

The Crouch boy peers up at you with nervous eyes. He looks so innocent, so pure. You want to crush him.

"He is devoted to the Dark Lord," Bellatrix says sharply, giving you a look.

You don't trust him. He's a Ministry brat, a dangerous enemy. But you aren't suicidal enough to argue with your cousin. "If you say so."

"I really am," he insists, and he gives you the smallest of smiles.

OoOoO

You sit in the garden, flicking ash from your cigarette and watching the albino peacocks strut among the plants. Footsteps startle you, and your free hand reaches for your wand. "Got a death wish, Crouch?" you snap.

His face flushes with color. "Sorry."

Your hand relaxes on your wand, and you focus again on your cigarette. "Meeting ended an hour ago. What are you still doing here?"

"I could ask you the same thing."

"Lucius is practically family," you say, snuffing the cigarette out on the sole of your shoe. "I'm allowed."

"Narcissa was showing me a book she thought I might like."

You snort. You'd almost forgotten that Crouch had been the curious Ravenclaw at Hogwarts, the golden boy with such perfect marks.

"You don't like me," he says.

"My God, you are clever, Crouch," you mutter, pulling a second cigarette from your pocket and lighting it.

He surprises you by snatching the cigarette away. "It's Barty," he corrects, inhaling the smoke only to double over in a coughing fit.

"Smooth, Crouch," you laugh, climbing to your feet and leaving him to it.

II.

He follows you around like a lost puppy. Once, you had been that way with Sirius. It almost hurts to remember.

"Will you stop, Crouch?" you snap.

"Nope."

Though you scowl, inside you're smiling.

III.

You find yourself face to face with your brother for the first time in years. In the distance, you hear the clash as Death Eaters and Order members collide. A battle wages, but it doesn't matter because Sirius is right in front of you once again.

"Regulus." His voice is barely a whisper, but it's deafening to your ears.

You pull out your wand, a curse ready on your lips. No sound comes out.

You hate him.

You love him.

You want to kill him.

You can't live with his blood on your hands.

"Regulus, come with me," he pleads.

Someone screams, and Sirius jerks his head towards the source.

"Go," you say softly, slumping to the floor.

He looks at you, mouth opened like he wants to say something more. Instead, he nods before rushing off.

You stare blankly at the wall before you, no longer aware of anything else in your surroundings. You had him. You could have killed him, but you were too weak.

"Regulus?"

You froze. It should have been an easy kill, and you froze.

"Regulus?"

Gentle hands find your shoulders, and you blink rapidly, barely able to process Crouch kneeling in front of you.

"Are you hurt?"

You shake your head even though it's not quite the truth.

"They got away," he reports. "We got one, though. She just crumbled. You should have-"

"Shut up," you growl, grabbing him and pulling him into a bruising kiss to swallow his words.

IV.

Crouch has no protests that night when you drag him into your bed. He doesn't fight for dominance as Sirius once had, and you love it.

"Regulus," he whispers, his voice breaking as you pin his shoulders, marking his neck with harsh bites.

"Shut up," you murmur, pulling his trousers away. "Just stop talking, Barty."

He laughs, and you don't understand what's so funny. You kiss him harder, savoring the way he tastes so different from Sirius. His lips are softer. His hands are smaller, more delicate.

He's different from your brother, so different that you almost forget Sirius.

He cries out. Sirius never would.

You growl, shaking your head. You can't think about him. There is only Crouch now.

OoOoO

You sit on the edge of the bed, exhausted and coated with a thin layer of sweat.

"You called me Barty," he whispers.

You pause, an unlit cigarette dangling from your lips. "What?"

"Barty. Not Crouch," he says, moving closer, his hand grazing your bare thigh.

"It won't happen again," you mutter, lighting the cigarette and inhaling deeply, letting the rush of nicotine work its magic inside you.

"I wouldn't mind if it did."

V.

He falls into your bed night after night until he becomes as commonplace as a pillow. Barty simply belongs there now.

You no longer try to hurt him. You no longer fuck him in hopes of forgetting your brother.

Something has changed. You can't pinpoint why or how, but you know it in your heart. With every kiss, with every night spent tangled in a mess of limbs and sheets, you are melting.

OoOoO

Barty curls against you, his lips working at your collarbone. "I love you," he whispers.

"I love you, too," you answer easily.

And you no longer care that Sirius is the only other person you've said it to. For once, Sirius no longer matters. There is only Barty and the great unknown that waits for you both.