Hm, this is awkward, English is not my first language. So I did my best. Tell me if I've done stuff wrong or made mistakes and, of course, what you think of it all !

Disclaimer: No.

Concerning Katara, Zuko, until now, has had to encounter four "Oh no" moments. What's an "Oh no" moment, you ask ? Well simply it's this moment you think, scratch that, you know you're screwed. So screwed, actually, that you only manage to say or think one dumb thing: "Oh no."

His first "Oh no" moment wasn't one exactly, per se, but it certainly felt like one.

It happened this time when our favorite firebender, along with Katara, was strolling around some market, buying fruits, rice –you know, the usual. Now I know what you think: something happens, they catch the eye of a soldier, Zuko is recognized, they're screwed, it's the end of peace among the gAang, they get captured, everybody dies, the end. Well that's not it, but nice try.

To Zuko, it sure seemed like it though, when he couldn't find Katara into the crowd of commoners buying supplies. Fear gripped his stomach so badly, he actually felt a bit sick –no exaggeration here, I assure you.

No need to panic, though, he found her little more than five minutes later –however to him, in his state of worry, it felt like way more–, perfectly safe, seemingly content and… Was that a guy with her ?! And Katara was… Actually chatting idly with him ? Smiling, giggling, the all lot ? What nerves, what… How could she just disappear on him to go flirt with some random boy ? Wasn't he the one to accompany her at the market ?

A little green monster that Zuko didn't know he had swallowed was roaring in his stomach. That, ladies and gentlemen, was the moment where our friend realized he was… Jealous.

He could only think of two little words following his sudden awareness of the fact: "Oh no."

His second "Oh no" moment was one of bigger realization than the last.

It was roughly two weeks after the market incident, as Zuko would now call it in his head. He had understood there had been no need to fret, as his waterbending friend had parted with the… The boy, without looking to see him again. Zuko was glad she had come to her senses ("Who dates during a war anyway", he had asked the wind some day). He now was sure his "jealousy" –emphasis on the quotation marks– had just been a one time thing, he had just felt pissed off because she had left without telling him, and the guy could have been dangerous, and there had been rumors of Firenation soldiers in the town, and she just shouldn't leave his side inside a crowd this big !

But ha ! Was he mistaken.

That night, two weeks after, then, he was washing dishes. Not alone, mind you, she was there as well. Playful banter was exchanged, nothing big, there was just this… This tension Zuko felt, between them. He didn't know where that came from, as they had become fast friends after their southern raiders trip, and he was half sure Katara didn't even feel it. So what was it ?

Still, they were washing, bent over the river, and this lock of hair Katara hadn't bothered to put up with the rest just kept coming in her eyes. It distracted Zuko, who had stopped washing to just stare at the damn lock. He even had had to stop his hand from reaching and tucking it behind her hear, at one point –what the hell are you doing ? He'd asked himself then.

Katara had noticed by then he had stopped washing the dishes and just raised her eyes towards him with a questioning look.

That was when he just… Froze. He wasn't doing much to begin with, having had stopped washing and all, but right there and then he even stopped moving, breathing, all of it. His tongue felt like sandpaper, his pulse was going berserk. He had looked her in the eyes so many times before, what was different ? Not the moon shining above them, it was way too cliché for Zuko.

Whatever it was, Zuko just knew. He knew why he had felt the way he had felt that day at the market, he knew why he had been looking at her more and more lately, he knew why Aang annoyed him when he was pining after Katara, he knew why he often wanted to sit beside her.

Was it… Love ? The world felt almost foreign in his mind, but somehow, it felt good to think it about Katara. Katara, who was still throwing him a questioning look. Because he was still frozen in front of her by the river. It was then that Zuko crash-landed back to reality, and realized the implications of his new discovery.

"Oh no."

There was also this one time, not long after he had understood he was head over heels for Katara. The gAang was eating, chatting, enjoying the midday sun. Katara had been homesick lately and had wanted to make everybody a water tribe meal –at the mention of it, Aang had made a gagging noise but everyone had agreed, not knowing what to expect, except for Sokka, who had been delighted.

Of course Katara had had to make Sea prunes for lunch –well, ocean kumquats. Zuko had never tasted something that horrid. He had wondered briefly why Aang had seemed so reluctant to eat but then, upon trying his first bite, had understood quite well.

Now with a mouth full of disgusting food –well everyone was eating it, especially Sokka, but Aang and him couldn't be the only ones to hate it, could they ? – Zuko had the choice to either swallow it and risk dying, or cleanly spitting it out and anger Katara.

He did neither, of course, because having waited so long to decide somehow made it worse: his saliva had mixed with the stuff and gooey mush wash now creeping up his nose.

Zuko made then the more undignified sound ever, a gargling cough of some sort, while choking and spitting bits of food everywhere. The ordeal had made him want to throw up, but he managed to stop himself just in time –his friends were already looking at him in horror.

Upon raising his head to apologize, his eyes crossed Katara's, burning hot with anger and just glaring at him like he had never been glared at before. As she opened her mouth to start screaming at him, she seemed to change her mind, though, and her eyes lost their sparkle of hate. She just looked sad suddenly. She excused herself from the group and went to her sleeping bad, a few meters away.

Zuko then knew he had screwed up. She just had wanted to reminisce home and he had thrown it back to her face (quite literally).

Realization dawned upon him as he thought it was the first time Katara had just… Left without a fight. He had really hurt her this time.

"Oh no…"

His four and last –to date– "Oh no" moment was some days after that. He had apologized countless of times to her, had promised he would try to eat her water tribe food again without reacting the way he'd had, had cooked for her to show her the difference between their type of cuisine, and in the end he had just had to make her laugh for it all to be forgotten–Momo had chewed on his favorite sandal, that was what had made her laugh...

So it was all back to normal between them (well, as normal as it could get knowing that Zuko was all too aware of his huge crush on her). They were back to teasing and chatting at night when they couldn't sleep, their sleeping bags so conveniently placed side by side in the camp.

One night, though not one of these nights since he was actually sleeping, he dreamt. Well, of course, as a human, Zuko often dreamt. But this dream, he knew, was not the kind of dream to have about your friend who was sleeping right there. When he awoke, he could remember only moans and "oh Katara"s and touch and incredible feelings and the smell of her invading his senses.

Zuko, now fully awake, opened his eyes to see everyone staring at him. Katara was beet red, eyes wide, and, upon seeing he was awake, juste got up and left camp without saying a word. Sokka was throwing him that kind of look which makes you glad you can't kill people by looking at them, and Aang looked mortified.
Toph and Sukki were actually snickering.

Zuko feared the worst. And there it was, when Toph just full out burst out laughing and managed to say between tears "Did you know you talk in your sleep, Zuko ?"

OH NO.