"One night of magic rush
The start - a simple touch
One night to push and scream
And then relief
Ten days of perfect tunes
The colors red and blue
We had a promise made…."
-Heartbeats by The Knife

Zuko was certain of only one thing: Katara had all the urgency, passion and heat of a fire bender. Every kiss he gave, every time he nipped at her lips, her neck, every move he made was met with just as much fervor, if not more so, and intensified and doubled each time.

This…really wasn't supposed to happen, the two entwined, gasping and moving together on his bed, hands trailing over each other, learning each other's bodies and forms. He was Fire Lord, and she was just some water tribe peasant.

But she was more than that.

He was more than that.

They were friends, and this one time, they'd be lovers. Somewhere in the back of his mind, Zuko knew they'd never speak of this again; it would be just this once. Mai would never find out, nor would Aang.

They'd consider it a mistake in the morning, surely. But this was a long time coming.

She gasped beneath him, and Zuko was certain he'd never heard anything more beautiful in his life. She was just so beautiful, everything about her, from her shape to her hair to her eyes to her voice, her personality. He loved the fire inside, longed for it from Mai. But Mai couldn't express herself so openly as Katara did.

But now wasn't the time to think about Mai. Now was for Katara, and making sure that this would be one of the best nights of her life.

Of his life.

How had this even happened? Katara was visiting by herself, just to visit. They'd had some wine- not much; Zuko never allowed himself to drink much. He wasn't a fan of making a fool of himself under any circumstances. And then they'd just been walking around the palace, talking.

He'd said something that set her off, yelling at him, and he'd…forgotten what it was like to see such passion from a woman; Mai never yelled at him. Slightly scolded, yes, but showed extreme emotion? Never. And Zuko was enthralled; a little scared, but enthralled more than anything. He couldn't help himself.

He'd kissed her.

And then it led to this, the two in bed together.

An hour later, it became obvious:

This had been a mistake. A huge mistake for both of them.

They were still in bed, neither speaking just yet. Katara had her eyes on the ceiling, and Zuko was watching her, studying her almost. She kept biting her lip and frowning, and Zuko half wanted to say something to comfort her, but…that could invoke the wrath of Katara, a very fearsome thing.

So, his best bet was to wait, and let her speak first.

"I can't believe we just did that," Katara said finally, causing Zuko to jump a little. She still wasn't look at him, still fixated on the ceiling. "That I just did that. Aang…. Aang is going to be so upset."

Zuko swallowed. "You're going to tell Aang?" he asked, clearly surprised. He figured this would just be…swept under the rug and forgotten about.

She whipped around to look at him. "You aren't going to tell Mai?" Oh no. He'd invoked the wrath of Katara; she was clearly agitated, her eyes narrowed at him. "Zuko, I heard there was talk of a wedding for you two- and you aren't going to tell her about- about this?"

Zuko sat up, sighing. Already he was starting to wonder if this was worth it, to have this to deal with- no. No; it had been worth it, to have the hottest, most passionate sex of his life. He'd never take that back.

Even if it was a terrible thing to have done.

Zuko acknowledged that. It was a mistake, a huge mistake. But… He couldn't tell Mai.

"Mai would be…crushed," he said finally. "And she'd probably kill me."

"Oh, so that's what you're worried about? Mai being rightfully angry with you?"

Zuko slumped forward a bit, sighing again. "No. I don't want to hurt her."

"Well, good job with that," Katara said sarcastically.

"Hey! Don't act like I'm the bad guy here!" Zuko snapped back, looking at Katara. "You were just as into it as I was!"

Katara seemed to shrink a little. "I know," she said softly. "…What do we do now?"

Zuko was quiet a moment. "I don't think we should tell Aang or Mai," he finally said. "This was a mistake, and we shouldn't have done it. We both agree on that."

"You got that right," Katara huffed. Zuko chose to ignore that, however hard it was to.

"If they knew, they'd be very upset. It'd kill Aang if he found out. You know it would."

Slowly, Katara nodded.

"Okay," Zuko said with a slight nod as well.

Uhhh…I don't know where this came from I'm blaming it on The Knife, for creating a song that is so wholly Zutara.

Please leave constructive criticisms.