#1 - Untold - They do not act friendly towards each other in public – it is an unspoken truth that their relationship must remain secret.

#2 – Brother - Katara was the first to notice how he looked at her – heaven forbid Sokka see it, too.

#3 – Safe - Toph has heard their midnight conversations of lonely childhoods and lost mothers; she has just chosen not to reveal them.

#4 – Song - Neither has heard music in a long time; it is a nice change from the usual chatter.

#5 – Alone - Sokka has known from the beginning – he just hasn't the heart to force them away from each other.

#6 – Kiss - Their first kiss was unforeseen and completely uncalled for, although Zuko would have denied it.

#7 – True - Katara gave up lying long ago, and finds it difficult not to confess when Aang asks where she's been.

#8 – Explain - Upon hearing this, Zuko tries to explain to the young Airbender what has been going on these past few weeks.

#9 – Mad - Coincidentally, this conversation does not go well.

#10 – Captive - The night Zuko is informed that Katara has been captured by his sister – his own sister - as a prisoner of war is the worst of his life.

#11 – Cost - It does not need to be spoken out loud – they all know that Azula will pay.

#12 – Vengeance - No one is quite prepared for the night they stumble upon Azula's camp, although Zuko welcomes the chance to avenge.

#13 – Fake - However much they pretend that everything is the same, none of them can ignore the changes in Katara.

#14 – Girlfriend - "I really did like you, Zuko," Jin tells him as they talk as just friends for the first time, "but your new girlfriend is, I must admit, prefect for you."

#15 – Giggle - Zuko falls face down in the mud, and everyone gets a surprise when he laughs at himself, along with Katara.

#16 – Lie - Aang accuses Zuko of falling in love with Katara, and although he doesn't mark it as true, he doesn't deny it either.

#17 – Fight - The arguments Zuko has with Katara are laden with heavy insults, although neither quite believe the insults they hurl at the other.

#18 – Bruise - The first time Zuko hits Katara is also the last.

#19 – Farewell - It is a goodbye they both wish they good avoid, but also a goodbye they both know is inevitable.

#20 – Promise - It is another unspoken truth that they will meet again.

I'm not sure how well these flow into each other. What do you think? If this one gets enough reviews, I might do a Taang one next.