Sifu Katara was the last waterbender from the Southern Water Tribe. She'd fought oppression in the Northern Water Tribe and, despite all odds, became one of the first waterbenders to master the craft. Her skill on the battlefield and in the hospital tents was world renowned. All of the founders of the United Republic owed their lives to her. She had trained the Avatar, defeated one of the deadliest firebenders ever, and knew the moon on a first name basis.
All before she was fifteen.
It was no surprise then, that all young waterbenders idealized her. The stories were miraculous enough to make any child fill with wonder, and they were all true. Kenna could vividly remember nights spent clutching her mother's knee as her ears were filled with tales of Katara's great deeds. The others in her group were congratulated too, of course. The Avatar's praises were sung just as often. Sokka was also a matter of pride amongst his tribesmen.
It was just that Katara resonated differently with Kenna. She was one of her people, born in the same land with the same bending in her blood. When Kenna heard that she was teaching waterbending in the United Republic, she had left home for the first time in her life to attend classes. It had been over ten years since Katara left for her adventure with the Avatar, but there were still no native born Southern Waterbending Masters.
Kenna wanted her sifu to be one of her people, born in the same land with the same bending in her blood.
The classes went well. Kenna had little experience, but she tried hard. Those nights toiling underneath the moonlight with Katara and the rest of the class became the best part of her stay. She began coming earlier and earlier to try to get more bending in, and hopefully to be able to talk to her hero.
It was quite strange to accidentally walk in on your hero kissing the Avatar.
It wasn't that Kenna didn't know she and the Avatar were together. They were married. Everyone knew that they were together! It's just... she'd never thought about her wise Sifu sitting on a table, legs wrapped around an airbender.
Maybe she should give her a break. She was still in her late twenties. She still had needs.
It was easier to understand that she had needs in her head than it was to actually see her acting on them. Katara pressed herself closer to the young Avatar, her hips grinding against his.
Kenna gathered up all her courage, opened her mouth to say something, and-
Promptly turned around and left.
Sometimes, it just wasn't worth it.
(Training that night was fairly awkward).