Written as an epilogue to "Someone Else's Hero" by afrai. If you haven't read that story, go do so now--it's three short chapters and completely worth the read. If you don't read it, don't blame me if this story makes no sense. Or if you miss out on an amazing fic.
Karin wakes to a familiar noise: the sound of Chad's heart beating.

(She has never told him how much this comforts her. She's become possessive of the hearts of those she cares about. Not because she worries about losing them to other people--she's got way too much experience with that sort of thing to get worked up about it, thanks. She worries about losing them to...nothing.)

(She has never told him how much his heartbeat comforts her. It would be awkward. She's pretty sure he knows, anyway.)

Tonight, though, there's something different. Karin stands up and walks to the window in her nightshirt. She's not sure what she expected to see, but the shape outlined against the dark sky is...not expected, no, but not surprising either.

Rukia stands in the dewy grass, the light from the moon and stars wrapping around her like the ribbons of her sword. She probably does that on purpose somehow. So melodramatic. She's lucky it suits her.

Karin opens the window, scrambles out of it, and drops the few feet into the grass below. She walks up to Rukia, and she folds her arms. "Five years," she says.

And then she's grabbing Rukia by the shoulder, shaking her as if it'll make everything settle into place. "Doesn't anybody teach you idiots how to keep in touch?"

In the background, Renji's shadow unfurls as he stands. It touches Rukia's shadow and melts into it. But Karin can see the shift in the quality of darkness where the shadows of two separate people overlap, and it's like there's something missing.

She feels strange, like she's dreaming, but her dreams usually have more blood in them. Not as much blood, of course, as Rukia's--she's sure of that.

"I..." Rukia stops. "We come as we need, Karin. This is what we are."

Karin smirks. "I know."

Rukia looks away, and for a moment their eyes don't meet. But Karin feels Rukia's hand settle, slim and light and more intriguing than comforting, on her hip. She covers that hand with her own, not much larger, and she finds herself wondering if her brother ever touched Rukia like this.

So she screams.

She has never screamed at Chad. She doesn't need to, with him. Her screams would be absorbed by him, and that's not the point. So she leans on him, and she buries herself in him, and sometimes she cries on him (without tears, of course, because she doesn't do tears), but she doesn't scream.

She's needed to scream. She's needed to scream at the sky, "Ichi-nii, Ichi-nii, you stupid fucking bastard," and feel Rukia dig those slender fingers coldly into her hipbones.

That's what Rukia does. She doesn't move, she doesn't back down, she doesn't comfort. She stands there and she holds on, and when she shakes, it's because Renji has grabbed hold of her by the shoulder and is staring at Karin, not pretending he doesn't understand, but at least looking annoyed about it.

In the end, Karin buries her face in the crook of Rukia's neck and shakes furiously. It doesn't end until Renji shoves her back.

Karin's throat is hot and choked, but she's not crying. "Thanks," she says. "You're pretty useful for pain-in-the-ass shinigami." Then she turns, and she walks back across the grass. She has a sense that she's leaving a piece of herself with each of them. She thinks it's better than hanging onto those pieces herself. After all, she already lost one piece when it turned out that Ichigo had a hold of it all along.

She climbs back in through the window and makes her way back to bed. "Hey," she says as she sits down, because she knows Chad's awake. "Don't lose that last piece."

There is silence for a moment, a good silence, a Chad silence. "I won't," he says.

His heartbeat takes her back to sleep. The wind whistles through the open window.