I started writing this story a few years back, but at that point I had been planning to quit fanfiction (after finishing my works in progress) and ended up deleting it along with many of my other barely started works. Well, it's kind of obvious that I haven't quit fanfiction, so here we go with take two.

Needless to say, this story is the expanded version of 'Atonement' from my Where the Ocean and Sky Collide collection. It will be a lot more serious than my usual stories, but I have some interesting twists and turns planned. I hope you will enjoy. Oh, and the cover art is by jesterry (will forever be grateful for participating in that particular Zutara Secret Santa. Yay for art gifts).

Prologue

Zuko struggled to catch his breath. His limbs felt like jelly, overwhelmed by the sensations and raw pleasure that had seized him just moments ago. Sweat clung to his body in a fine sheen—clung to both their bodies. Katara lay panting underneath him with her legs spread. He shifted to hold himself up on his elbows, skin sliding against her skin in sticky dampness as he looked down into her eyes. The fog was beginning to clear in his mind—in both their minds—and what he saw in her gaze had his heart clenching in a trap of unease. She looked scared, almost horrified, as if she couldn't believe what she had just done.

"I—" he began, licking his lips.

Katara shoved him off her before he could finish his sentence. The tiny hiss of pain she made when he slid out of her sounded far too loud to his ears. He hit the ground: naked, graceless. She snatched up her clothes and gave him a wild-eyed look as she stood to her full height, like an animal about to bolt. In that moment he could see her shame, her lust, her naked fear.

"Don't you dare tell anyone about this," she said in a shaky voice, trying to appear intimidating but only succeeding in looking small and vulnerable. "I'll know if you do, and I'll—I'll—" she compressed her lips together, trying to get a hold of herself.

Zuko reached out for her. "Katara—"

"Don't!" she cried, flinching away from his hands. "Just don't—don't touch me."

He paused, not quite able to hide the flicker of hurt in his eyes. "Fine," he said flatly, "but before you start turning me into the monster who stole your virginity, just remember that you were the one who kissed me first."

She stared at him through overly bright eyes, but he just turned the other way. He didn't want to give her the satisfaction of knowing that she had upset him. He felt used and dirty, like some plaything to be enjoyed while the moment lasted and then tossed aside when reality came knocking again. It was humiliating, wounding, and a part of him wanted to shout at this girl; to demand who the hell she thought she was that she could just string him along like this, playing hot and cold with his emotions as if it was nothing.

"Just go away," he muttered when she remained silent. "You obviously want to pretend that nothing happened, so forget it. Leave. I won't tell a soul."

She didn't move.

Zuko repressed a sigh and turned back to look at her. "What?" he snapped. "Why are you still here? What is it that you want from me?"

It was an echo of his earlier words—the frustrated words he had thrown at her when he had first cornered her against the mural wall, desperate to understand why she refused to accept his apology and let them both move on. Katara must have recognised it too, as her eyes flickered to his in a skittish glance. However, this time there was no impulsive kiss, no blood-tingling fire. She just stared at her feet, clutching her clothes to her chest to hide her naked body. He let out a small breath. She wasn't even going to answer.

Katara tugged on her robe and made her escape, leaving him alone in the mural room. Zuko didn't bother to follow her; instead, he placed his head in his hands and closed his eyes. It was as if all the energy had been drained out of him. There was no comprehending what had just happened. Everything had spiralled out of his control so quickly, and now he just felt confused. So torn between feelings of anger and desire and shame.

"Stupid," he muttered. "So stupid."

He should have never kissed her back. He should have never allowed himself to be caught up in the moment, but it was too late to reconsider his actions now. The damage had already been done; he'd had sex with Katara. He'd let her take from him the last of his innocence, even as he had snatched away her own. Regret was a bitter taste on his tongue, choking and sickening.

He just wished he could forget. He wished he could erase everything and start fresh.

But he couldn't forget. Not the next day, nor the day after. She had finally left him alone and stopped being so openly antagonistic, but that did little to comfort him. Every glance was a reminder. Every accidental brush was a memory of frantic kisses; of racing pulses and clumsy hands, touching and being touched in places that had never been touched before. Zuko hated it. He couldn't stand being reminded of his mistake.

Of how utterly ashamed she made him feel.

But it wasn't until six weeks later that he realised the full consequences of what they had done that night in the Western Air Temple. His father and Azula had both been defeated. Everything was supposed to be resolved now. Happy. Zuko had been formally crowned Fire Lord and his first speech had been well received by the people. All he had to do now was get through the main inauguration party. Everyone had gathered, all there to support him—even Katara was present. Except then Toph had made that odd comment and Zuko had just felt sick, his insides trying to force their way out of him as panic and dismay gripped his heart.

Because Toph had sensed two heartbeats inside Katara, and that changed everything.

So, if you've read the original you'll realise that I cut the entire sex/smut scene. FFN is pretty strict on its ratings these days, and I just prefer to not get too explicit anyway.

To clarify a few plot/canon divergence things, Zuko and Katara never became close friends in this AU's timeline. They did not go together to find Yon Rha, nor did she fight beside him to stop Azula. Instead, they did the naughty together at the Western Air Temple after a heated argument, freaked out about it (as we saw), and pretty much avoided each other as much as possible after that. So, yes, their relationship is still quite tense and there are unresolved issues.

And that brings us to where the real story begins …