Jetara

Jetara is a Het ship between Jet and Katara in the Avatar: The Last Airbender series.

Canon
Katara first met Jet after she and the rest of Team Avatar accidentally walked into a Fire Nation camp. Jet and his freedom fighters jumped in to help them. Katara immediately developed a crush on Jet and blushed as he helped her up into the treetop hideout. She was very impressed in Jet's skills and Jet was impressed in her waterbending ability. They also sympathized with each other over losing family members to the Fire Nation.

While the group was staying with Jet, Katara's brother Sokka witnessed Jet attack an old civilian from the Fire Nation. Katara wanted to hear Jet's side of the story and believed him when he made up evidence of the old man being armed. Katara refused to believe Sokka's warnings about Jet until she saw that he was trying to flood a village with innocent people. Jet insisted that it was a necessary sacrifice but Katara cried before freezing him to a tree. She told Jet that he was sick before leaving him behind.

Months later, Team Avatar went to Ba Sing Se to look for Appa and Jet went there as a refugee. He found a poster of Appa and approached Katara but she immediately froze him to a wall and told him to go talk to some other girl. However, the rest of Team Avatar insisted that they let him help. Toph asked Katara if Jet was once her boyfriend and told her that she was lying when she denied this. It was eventually revealed that Jet was brainwashed by the Dai Li. Sokka suggested that Katara kiss him to jog his memory which disgusted her. She instead healed him which helped him regain his memory.

Jet later took the group to Lake Laogai to help them find Appa. However, Long Feng and the Dai Li appeared to attack them. Long Feng also spoke a trigger word to reactivate Jet's brainwashing. However, Aang managed to remind him who he was. Unfortunately, Jet was hit by a boulder and fatally wounded. Katara desperately attempted to heal his wounds but Jet insisted that he would be okay and told her to leave and find Appa. Jet eventually died from these wounds, but Katara finally forgave him.

Fanon
Jetara is a mildly popular ship in the Avatar fandom. Some who ship Jetara also ship Zutara and use it as evidence of Katara's type and how she typically reacts when she is in love. There are some fans who interpret this relationship as being abusive despite the fact that they patched things up. Jetara commonly rivals the Kataang ship and occasionally the Zutara ship as well.

Trivia

 * According to Avatar Extras, Jet was Katara's first kiss, but they never kissed on screen.