Just an Oc in an upcoming fanfic. She was super fun to color, by the way.
She's dead, just so you know. More or less sent back by Aang to be someone's spirit guide (considering she was extremely in tune with the spirit world before she was killed). Her help was required in order for Korra's own spiritual teacher (Unalaq, also Korra's uncle) to learn, therefore being an indirect aid to the Avatar and her struggles.
Before her death she was engaged to a firebender, whom she met during her travels, and had a place in the newly formed Northern council due to her spiritual ties. When Aang suffered from assumed foreboding in his dreams, unable to contact Roku due to the mental discomfort, Mita provided a clear explanation. That was probably the most exciting and significant event in her short lifetime.
At age 20 she was killed in the Northern Water Tribe, having been forcibly drowned by a stronger bender who'd held her underwater. Her facial scars have no ties to her death, and were gained from the practice of pulling water out of thin air, only to have it whip back by recoil as she tried to bend it. She was quite clumsy, but did master it. Unfortunately one unusual talent wasn't enough to defend herself from someone with more experience.
Mita © ~Evangeline73
LoK and AtLA © Nickelodeon