given the average lifespan of a gurlanin is 700 years, it is entirely plausible for her to be around for both Knights of the Old Republic and The Old Republic

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given the average lifespan of a gurlanin is 700 years, it is entirely plausible for her to be around for both Knights of the Old Republic and The Old Republic
In the end, like watching Frieren: Beyond Journey's End itself, I broke. here's some scattered thoughts on an au for Tari:
Licht Falke (bright hawk) and Nett Helfer (nice/kind/cute helper) Dral Galaar (bright hawk) and Tari Novhret (beautiful companion)
Nett is a demon who was raised by an adventuring guild, though most mistake her for an elf given her horns are quite small, easily hidden by her hair and helmet, and her ears are notably large and pointed. she is particularly fond of support spells, and suppresses her mana as she dislikes being referred to as a mage
she's traveled nearly the entire world, but she tends to stay up north, even despite her distaste for the cold. she assisted the Hero's Party by offering them information about the Demon King. she has a habit of sending Frieren plants and other materials, including spells and grimoires she comes across as a way to try and win Frieren's trust
"You're a demon, yet you act like a human."
"Should hope so, it would ruin all my sibling's hard work otherwise."
I think it would be funny if the two music genres Tari is most prone to listening to if left to her own devices is metal and electro jazz/swing
it occurs to me that no matter the setting/franchise, Tari has a terrible taste in who she decides to follow around. it's almost always grumpy and not very nice
the problem is very much that despite her severe anxiety, Tari has little to no self preservation. that and she is extremely useful -- she has a bit of a nasty habit of being able to get into places she isn't supposed to and she either Knows Things or can dig up that information with relatively no fuss
she also just likes having someone she can hide behind if she ever gets upset. like you made her cry and now you have to deal with the consequences
(and there is the fact that she does in fact find it Very Fun act like an annoying younger sibling, knowing the person can't do shit because she is incredibly useful, and if they get rid of her they'll loose their information source)
getting threatened with a spray bottle because Tari is notorious for expressing her self doubt (it wouldn't last more than an hour)
modern Earth Tari who has never once set foot in an academic institution lower than a college or university. the only reason she has a legitimate college degree is because Revan somehow managed to convince her it was a good idea. she did have to enlist the help of Revan's brother Navree to help fudge a few bits of paperwork, but it's fine, really it is
Tari doesn't trust Malak -- or at least, not entirely. he doesn't seem to like her very much, and she has a rather nasty habit of showing up out of nowhere to scare him whenever she feels like it. she treats him more like an annoying younger sibling and he has to put up with it but he's painfully aware that Tari has and can get a lot of valuable information
Tari definitely knows it was Malak that got Revan "killed". anyone can see just how resentful Malak had become of Revan towards the end. yet for all Tari's distrust of Malak, she felt she had nowhere else to go. she was much more defiant and frustrating to work with, but she did provide valuable information, so Malak was once again forced to put up with her bad behavior
Tari also knew Jaq. Jaq was something of Revan's Favorite for some time, so it's not surprising that they would end up becoming at the very least familiar with each other. like Malak, Tari treated Jaq like an annoying younger sibling, but he was far more indulgent of her so she ended up with a far more favorable view of him. when Jaq ran away, Tari likely knew exactly where he planned to go, and she kept that to herself
which means that Tari showing up during the course of KOTOR II causes Atton no small amount of stress. still, she never gives any indication she knows who he is -- or, well, was -- and the most she demands are head scratches and letting her use his bunk whenever she feels like it, so it's definitely not the worst outcomes for him by any means (Tari also doesn't seem to like or trust Kreia, which does a lot for her in Atton's eyes)