Catra's heartbeat had sounded in Adora's head like a familiar melody for as long as she could remember. She did not so much hear it as she simply sensed it, as if it were an extension of herself. She had felt it enough times to know its pace and she took both solace and pride in the privilege of knowing.

At one point, it had gently beat in time with her own pulse. She had felt it attune to hers in the still nights they lay against one another, front to back, the brisk patter of Catra's heart slowing to meet the steadiness of hers—the way it did only for her. It had been that way forever, it seemed, and Adora had accepted it as a fact of life.

For a while now, though, the two rhythms had been at odds.

At first it was only a hiccup every once in a while, in the same instance that pain or jealousy or anger flashed behind Catra's two-toned eyes at a passing comment from another cadet.

Then it had increased to stammers, whenever Adora got a step ahead in their training and the prospect of Force Captain loomed ever closer—for one of them, at least.

The time that Adora finally appeared with that cursed badge on her chest and had to break the news to Catra that, no, her squad would not be entering the field with her, Adora felt their metronome fail. It was only for a short time—only until Adora surprised her with the keys to a stolen skiff—but that was the beginning of the end.

Everything had fallen apart that night that Adora left her to search the Whispering Woods—I'll be back before anyone knows I'm gone, she'd said, and maybe an Adora from an earlier time would have sensed Catra's unspoken answer: I'll know you're gone—but she hadn't. She'd been too preoccupied with the sword.

Since then, well…it was like their bodies were tuned to completely different frequencies entirely. Once Catra had vanished into the smoke at Thaymor, Adora had forgotten altogether what it was like to live in synch with her other half.

Adora supposed she should have seen it coming.

She should have known that it was inevitable for them to grow out of the habit of coming to one another in their darkest and softest moments, without words but with full understanding between them, only a simple goal in mind.

Adora couldn't remember the first time she'd pressed her palm to the curve of Catra's sternum and felt the throb of her heart beneath her touch. She only knew that since that indeterminate time, she'd done it on more occasions than she could count.

They did it for calm. They did it for comfort, for understanding, and for forgiveness when words were beyond them. They did it after they had gotten into a spat over a sparring match, and Adora wanted Catra to know that she was never second best to her. They did it after a run-in with Shadow Weaver left them both shaken and one of them aching all over, and Catra needed to know that she was worth it, no matter what that witch said. They did it after Adora scored less than perfect on her cadet evaluation and she needed something steady to ground her in the midst of shaking hands and trembling breaths and madly swirling self-doubt. They did it even when Lonnie and their team poked fun at them for being too attached to one another, because those goons had no idea how deep their attachment could possibly go.

There was just an inexplicable comfort in knowing that the other had a beating heart and breathing lungs and feeling hands, and a thinking, working mind, even if the inner machinations of those things remained a mystery. There was both the relief of familiarity and the value of a newfound secret in such a feeling that the girls could find nowhere else.

They each took solace in the knowledge that the other had a unique, personal, constant perspective and even if they could not see at that moment what that perspective was, they knew with full clarity that it existed and that was enough. They each knew that the other was a distinctive, precious person that fit against them like a second half, and that was enough. They were alive, and that was enough. They would acknowledge that and consider that and validate that all in a simple motion that had never lost its poignance, even after years of doing it.

And even after years, Catra never lost that tentative, almost reverent look on her face that accompanied the pause before they touched; the moment that one or both of them hovered with one hand raised, half-outstretched toward the other, asking permission that had never been needed but still felt right to receive.

The instant that they touched, though, was foremost of the moments that never lost their power. When they met, a shock went through them both as if they'd taken a hit in weapons training. Usually they gasped, and usually Adora pressed her eyes shut to center herself around the sensation of her best friend's life beneath her palm. Always they let their unsteady breaths out as one and in that moment they drew closer together, feeling the rightness of their companionate hearts.

Now, though, all that was forfeit.

Adora was stuck imagining the clash of their two hearts, not just in the fact of their rhythms but in their intangible paths as well. Every time she met Catra across the field of the war she felt it, like a stutter in her chest. She wondered if Catra felt it, too—she imagined that was the moment's falter in the rage in her eyes, like a spark dying behind the gold and the blue.

More than once, she was tempted to reach out in that motion that had drawn them together all those countless times before: raising her hand to hang in between them with fingers half-curled in a plea that only they knew.

She never did, because seeing Catra reject that plea would be more painful than any seizure of her heart—and she knew that Catra would reject it.

She never did, until now.

Now she had no other option. Now Catra was facing her across the meager span of the storage room, face pulled into a frustrated scowl, not listening to her when she said they had to leave, now, or they would be consumed by the portal that Catra had unleashed in blind fury at her. Adora had tried every way she knew how to convince Catra to escape with her, but her words practically died on her lips for all the good they did. The worst part was that she could see that Catra remembered; she knew what was happening, she knew that Adora was right, but she refused to cooperate in spite of it—or maybe, Adora realized, because of it.

She had felt the dissonance between them for long enough to know that Catra was not willing to listen to her anymore. She was not willing to concede to her ever again, because she felt like she'd already been playing second fiddle her whole life—Adora didn't have to read into their broken hearts too far to realize that.

So now she had nothing else left to do. She'd glanced at the crate of stun batons on the floor beside her, but she knew that option was more likely to stop Catra's heart than turn it to her cause.

So she did the only thing she could think to do.

"Catra," she said one final time, pouring all of her desperation and urgency and brokenness into that single utterance, begging some part of it to cut through this hardened mask of anger Catra had built up, to reach the girl she knew. She said it, and she raised her hand.

At first Catra closed her eyes and whipped her head to the side to avoid the sight of it, like she'd been struck. It tore Adora apart to see her react with such pain to a gesture that had once meant healing to them, but she didn't lower her hand. When Catra cracked open an eye just enough to regard it miserably, Adora saw tears shining there.

"Why can't you just stay?" the feline demanded in a voice too broken to be harsh. "We have everything we've ever wanted." She was hugging herself, shoulders taut, claws extended and pressing into the skin of her arms.

"It isn't real, Catra," Adora insisted as gently as she could, still imploring with her eyes, still reaching with her hand. "As much as I wish things could be simple like they used to be—" Her throat closed up as it hit her just how much she did wish, desperately, that they could go back to the way it was before: natural, in tandem, together. "—they just can't. The only thing that's real is—" Suddenly she shifted the course of her hand and instead of placing it to Catra's chest, she took the girl's hand decisively and brought it up to the bone between her own breasts. "—is us."

Catra's breath hitched the way it always did when Adora's heartbeat thrummed under her palm, only this time tears followed, and her hand was trembling. Adora never let go of her. Instead she moved closer, guiding Catra's other hand up to press it over the first. She could feel Catra's pulse through her fingers gripping her wrists, and though the rhythm fought against her own, it was temporary.

Catra closed her eyes again and lowered her head and Adora could practically hear her teeth grinding together as the feline's focus narrowed to Adora's heart and only her heart, unwillingly yet longingly.

"I won't leave you behind again," Adora breathed fiercely. The hum of her voice ran down Catra's arms and she saw the girl shudder, her tail lashing wildly behind her.

Catra's fingers clenched in the fabric of Adora's shirt. "Adora, I can't—" she began in a strangled voice.

"Stay with me, okay?" Adora cut her off gently, in the same words Catra had spoken before. One hand slid from around the girl's wrists and she instead lifted it to Catra's chest, finally, the way she had wanted to since they'd lost each other; lost their rhythm.

Adora had found her again, and she would not lose her a second time, no matter the cost. She would give her life to see Catra free of pain; strong in herself; following the beat of her own drum. She could not guarantee that now, but she could see the first step as clear as day.

"Stay with me, in the real world," she continued earnestly. She could feel her life force and Catra's mixing and stumbling over one another through the touch of their hands—out of synch for so long that it was painful to recover. Through the constricting feeling in her chest Adora voiced the words that she had never gotten to say: the ones she had rather die than let Catra go without ever hearing from her: "I still want you."

That made Catra look up, blinking as if the world were just now coming into focus. Her eyes met Adora's and they were full to the brim with guilt and regret and stabbing, twisting pain and uncertainty and the words fell from her lips with the weight of old distrust: "You promise?" Catra's voice was hoarse and barely audible over the distorted, cutting static noise of the portal that they knew was drawing ever closer, just beyond the door.

Adora let out the breath that she'd been holding for the last minute—the last hour—the last eternity, since she and Catra had been separated—and she felt their hearts beat as one for the first time since then.

"I promise," she answered, breaking the link between their chests to throw both arms around Catra, more relieved and more full than she'd ever been in their perfect, imperfect past. Then she pulled back and slid her hand down to clasp Catra's, and the other girl squeezed back in an answer that needed no words to be understood.

"Then let's go," Adora replied, tears in her eyes and a smile on her lips, before she led the way out of the room and into the world that the portal was tearing apart just a step behind them.

This was perfect, Adora thought as they ran. This was the reality that she would fight for—Catra's hand in hers, following her to safety; the throb of their heartbeats racing as one as they outran everything rising to destroy them.

The feeling of her precious other half sliding into place in her heart again—

Finally.