Coexistence (n.): to live in peace with another despite differences, especially as a matter of politics, nationality, social customs, and ideology.

He's lean and wiry beside her in bed, and she would run her fingers over the ridges of muscle and bone if she wasn't so distracted by the worried look etched across his face. His lips are set in a hard, thin line, and she listens to him breathe shallowly in his sleep. His black hair is a mess across his forehead and his closed eyes are tight and restless, flickering dangerously beneath the thinly veiled lids. In the dark his scar is barely noticeable, but the puckered pink flesh seems to spasm as he slumbers; even in his dreams peace eludes him.

She finds herself wondering what kind of monsters haunt his nightmares—his father, his sister, his mother? Even though she's spent every night in his bed for the last eight months, she knows precious little about him, and sometimes it scares her but mostly she accepts it for what it is—accepts him for who he is. She shouldn't care for him and she certainly shouldn't trust him, but she has no one else. He has become her entire world, and her desire to know more about his past is outweighed by this new and marrow-deep need to coexist with him. Really it's quite a bit more than just coexistence at this point (co-dependency almost), but it's messy and the boundaries are sketchy and she has no better word for it—or at least she doesn't want to admit to what it truly is.

The line of his pelvis is sharp where the sheets pool around him and she follows his contours with her fingertips, delighting in the wave of shivers that arc beneath his skin. Still he does not stir, and she frowns. She can't decide if she's relieved or disappointed by it; lying awake at night is less distressing with company, and maybe if she were otherwise occupied she wouldn't be pondering over the gravity of her situation and what it is that she's got herself into—sleeping with the enemy. Her father must be rolling over in his grave.

In fact her family is the reason she's here to begin with. No, wait—scratch that—his family is the reason why she's here; why she's alone with no one to depend on but him. Sometimes it makes her sick, lying awake at night thinking about the state of the world. The Avatar has still not surfaced and Fire Lord Ozai has taken over most of the Earth Kingdom with the aid of Sozin's Comet almost four years ago. Her father had died in that epic battle and her brother had taken off to the north-east just a year ago, gathering with the rest of the Water Tribe forces and what remains of the Earth Kingdom army, leaving her behind.

It wasn't until her eighteenth birthday that she had met the banished prince. He was looking for a guide to the South Pole, and she was looking for a way out. Neither had intended for their relationship to progress beyond that and neither had fought the inevitable when it had. He had not forced her, and she had not thrown herself at him. The reciprocity was mutual; it had become a relationship of convenience. It still is.

It isn't like he's her soul mate; she can barely stand him at times. He can be oppressive, malicious, and downright pompous, but underneath those layers of arrogance and corruption is a man possessed of a deep sense of honour. She can't fathom why the conflict of nobility and darkness inside him makes her worry, especially when he's made her feel more alive these past few months than anything or anyone. She convinces herself that it is lust, not love, that draws her to him. He is Fire Nation and she is Water Tribe; they are never meant to be. No, he is merely her one and only chance to save her brother and find the Avatar; he is a means to an end.

"Bad dreams?" His raspy voice in her ear causes her to jump, and she bunches her fists underneath her chin.

"I'm fine," she whispers, her breath hot on his neck.

It's a lie, and he knows it.

"Mhm." His strong arms suddenly snake around her waist and pull her in close. "We'll find your brother," he murmurs into her hairline, and takes a deep breath. "I promise."

She pushes away and rolls over onto her side, her back curving into his chest. He sleepily nuzzles his chin into her hair before shaping her body against his. It's a simple gesture, heart-warming and sweet. With her cheek braced against closed palms she tries to shift away, but he only pulls her in closer. Her bottom lip trembles and her eyes threaten to water. His simple act of kindness has no business making her eyes tear up at the corners; his arms wrapped snugly around her waist have no right making her feel so safe and secure.

"Prince Zuko!" Lieutenant Jee calls loudly from outside the door, shattering the moment. "We need you up on deck, sir!"

Zuko mutters unintelligibly into her hair, fully roused from his fitful slumber—the tell-tale evidence jabbing at her lower back. At first he appears confused, still being drawn out of the treacle grasps of sleep, but then his instincts kick in and he quickly disentangles himself from her body and stands to his feet. She can see the outline of his naked form at the foot of the bed and she faintly wonders if he will eschew his clothes entirely and just run up on deck. Instead he fumbles for a tunic and a pair of trousers, dons them swiftly, and walks steadily to the door, following the sounds of the crew and the cracks of lightning from above.

The spirits only know what's going on outside. From what she can gather is that it's raining, but it isn't a storm to cause worry, and the likelihood of them being attacked by Fire Nation or Water Tribe is just as doubtful. It could be a distress call; sometimes Zuko answers them, but they have been few and far between these days. The Fire Nation owns the seas, just like everything else.

She pushes herself up into a sitting position and waits—waits and listens. She can leave any time she likes; she's not his prisoner. She's kept her Waterbending a secret, and she's trained herself to become quite good at the art, though the need for a master is apparent. Still, there's no way Zuko could possibly stop her at sea; she could leave. But she's not waiting for the opportunity to escape; she's waiting for him to return. She tells herself that she's with him because he'll help her find her brother and—who knows—maybe he will find the Avatar. But what then? Can she make her brother come with them, board a Fire Nation ship and make peace with an enemy prince who beds his sister every night? Can she handle that kind of shame? And what if her brother isn't even—

She banishes the soul-annihilating thought before it can fully formulate in her mind. She doesn't want to think about the what-ifs and the most-likelys because even if she finds her brother and he joins them and Zuko somehow finds the Avatar, what can she do? Zuko will take the world's last hope to his father and bargain for his honour. And then what will happen to her? On this ship she can be his mistress, his not-so-dirty secret, but she isn't about to become a spoil of war to be paraded around the Fire Nation palace. She would kill herself before that ever happened. But what if she already is a war trophy, some stupid conquest?

Sometimes she just wants to throw herself down on the floor, beat at it with her fists, and cry. If there's no one and no hope left, why continue, why struggle against the inevitable? Why not purge herself of all emotions and just let go?

There's nothing left to worry about she tells herself, but people aren't things and she can't force them from her mind no matter how hard she tries, no matter how much it hurts. The problem is that it hurts too much; it bothers her and worries at her stomach in the middle of the night. What does her family think of her in the spirit world? Are they ashamed? Disappointed? Is she with Prince Zuko because she has no hope or because hope is all she has left?

She has so few misgivings about building her life around him now that it frightens her, sneaking up on her when she least expects it. In the dead of night she'll wake up in a cold sweat and reach out for him. Deep down, she wants him to push her away, to berate her, but more often than not he takes her into his arms and soothes her, holding her gently until her tremors dissipate. Those are the times that she's not thinking about how this is all a game or who's using who but how they need each other—how they rely on one another.

She's long past all that crisis of conscience nonsense; she's chosen him and this life that they live together. But choosing him is not what worries her. She knows that deep down he is an honourable man who has the potential to be a great man, but he doesn't see the world the way she does. He does not see how the Fire Nation destroys as it consumes. He looks for the Avatar not to bring balance to the world but to restore his honour—honour that he still maintains must be given, not earned. And she—she enables him. But is her fear about losing herself to this man worse than losing the morals she's lived by her entire life?

The bedroom door creaks open and Zuko is standing in the backlit doorway, dripping wet with rain and the spirits only know what else. The light from the hallway illuminates his face; he has the look of a man broken, lost and found, driven and hopeless all in the same breath. Once the deer-in-headlights look has left Katara's face she's up out of bed, pushing the door shut and pulling off his clothes until he's bare and dry again. His presence alone, having his body in her arms in the darkness, feels like aloe over sunburn; his long-fingered hands push her flimsy tunic up over her head, lips press open-mouthed kisses to the back of her neck.

His palms lower to her hips, and he traces her body with fingertips that skim along the low dip at her back. His hair is loose and wet and falls around his face, woven through by her slender fingers that hold him still against her throat. His kisses are long and languid, burning her very flesh, and she moans for more. From there it's all a tangle of hands and searing kisses until gravity takes hold and pulls them close, setting their world on fire. Heat rises between them, licks at their skin, and spreads its sweet torture beneath this slow-burning haze.

She's impatient for more, but he catches her wrists and brings her palms to his chest while his rest on her hips. His body presses against hers, thrumming with life, and she wonders if he will pin her up against the wall and take her right there or on the floor, rutting like two wild animals. But he kisses her instead, long and thorough and sweet, leading her back towards the bed. He will love her soft and slow and kiss her until her breath comes short and ragged—until both their pulses beat rapid and staccato, and they beg for release. And as he eases her back onto the mattress, trailing hot, open-mouthed kisses along her throat and the hinge of her jaw, she sighs into his hair and thinks that maybe he is the only real thing left in her life.

He presses into her, bodies flushed and heartbeats shared-warm, and they make love. It's not the raw heat they often share but a passion that is burning and lingering—emotional. They pour their hearts out into the act—an act that is no longer a perfunctory ritual but a shared experience. It is a dance that only they know the steps for, a song that only they know the lyrics to, and when they finish throwing themselves into each other—their doubts, their pains, their frustrations—he wraps her up in the blankets and in his arms. They quickly fall asleep this way, touching foreheads, and for the moment it soothes away the terrible guilt that hides behind her heart.

-x-

Author's notes: This was written for an AtLA AU challenge, which is why this piece isn't as lyrical as it could be. It has a bit of a stream of consciousness feel to it because Katara's thoughts are jumbled and erratic, jumping all over the place, much like my own ninety-eight percent of the time. Part II will be taken from the same timeline, except from Zuko's PoV.

I'd like to thank Masayume85 for going over this chapter for me. Merci, mon ami. ^_^