Here's my submission for Toko week. I don't like it as a romantic pairing but they would definitely be good friends. Takes place some time after the final battle.
-The life after-
"You know you can't stay here forever." Zuko said to Toph when she was done beating up his guards.
"Why not?" She asked as she collected the spoils from her win.
"Well for one it's unseemly to have my finest guards beaten to a pulp by a little blind girl." He said trying to conceal a smile.
"And second I'm sure your parents miss you."
Here face darkened from it's usual level of happiness. "I don't want to see them." She said indifferently and started to walk away.
"But I'm sure they must want to see you!" Zuko said before he heard the great door to the front of the palace slam shut.
He looked down at his guards who were piled up in a heap.
"Get up you lazy bums." He said and started to follow Toph.
He finally caught up with her and followed behind, she didn't stop or even slow down when he started talking again.
"Toph you know you can't stay here forever." He said and gestured at the royal palace vaguely.
"But you're the fire lord I'm sure you can let me stay here as long as you want."
"That's not the point. Mai and I well we err… It's just kinda awkward being err… you know intimate with some one when there is a twelve year old girl listening from the next room."
She slowed down and finally stopped. "You mean you don't want me here?"
"No no! It's just uhh…" He remembered her lie detector abilities with a pang. "Yes Toph, you're my friend but… I'm married now and there's just no time for me to hang out with you anyway."
It took her a long time to answer. She was looking down at the floor and her bangs obscured her face. "Oh… Alright I-I'll just send a message to Aang and see if he want's to hang out." The tone was unmistakable but Zuko could still not believe it. She's crying?
Before he could even think of an answer she started running down the corridor. "Wait Toph I-" But he was cut off by a huge Earthen pillar the jammed right through the floor boards and up to the ceiling effectively cutting him off.
-Later that same day-
Zuko knocked on the door to Toph's room quietly. The sound behind the door ceased and it sounded like someone jumped off the bed. "Toph open the door."
"I'm leaving tomorrow, Aang said he would pick me up on Appa, I have to pack my things I don't have time to talk."
"Open the door." He repeated determined to talk to her.
"No."
"Then I will kick it down."
"Go ahead it's your door."
He groaned. The council is already angry about having to pay for the corridor now a fancy door too?
"Please Toph?"
"No."
"Fine." He squared his shoulders and took a few steps back. Then kicked the door in.
"Fine you're in now get out." She said turning back to her pack on the bed. She had few enough possessions. There was the Earth rumble belt, the clothes upon her back, another set of fire nation clothes, her headband and the pack she carried it all in.
"Come on Toph let's talk about this."
"I don't want to."
"Toph I know you might hate me for sending you away but Mai and I need our privacy and you need to see you're parents… And I really don't want you to go…" He added in quietly afterwards.
"Really?" She asked trying not to sound too excited.
"Yeah you're my best friend." He said truthfully and she knew it.
"Thanks." She said wiping away a tear.
"So no hard feelings?" He said extending his hand out.
She grabbed it and proceeded to crush his knuckled in an iron grip.
"Not anymore." She said and released his hand.