From the 3rd DLC Character Voting page:

As popular figures in nationwide folktales, a children’s television adaptation of Annie and Sagan’s adventures was inevitable. The show’s success lies in its pair of live action hosts, who are as convincing as their cartoon counterparts. Though what the public learns about the real Annie might surprise them.
Annie is a seasoned fighter who has been around for a long time, acquiring many skills and powers along the way. Her sword is forged from a meteorite and can channel the power of the stars in its sweeping cleaves. Her right eye bonds her to her Remote Parasite and partner, Sagan, who grants her powers of a galactic motif. While some of her abilities carry more of a sparkly magical girl motif, Annie tries to execute them with the same sternness.

From "The canon info thread" on Skullheart Encore forums:

-Annie is several-century-old. Her immortality was gained when her parents wished on the Skull Heart so that Annie would never have to experience the hardship of adulthood, thereby making her forever a child.
-She has had many different weapons and abilities throughout her life.
- Sagan, her remote parasite. keeps her right eye in his mouth.
- She’s physically not able to swear due to her condition
- She is familiar with Double due to her experience fighting Skullgirls
- Annie has encountered a lot of Skullgirls and has killed a lot, but not the same a lot. She’s seen the cycle multiple times and seen how they become stronger each time and is looking for the underlying source now. - The Annie of the Stars show is very similar to the Super Mario Bros. Super Show with live action segments with cartoons and PSAs and commercials in between.
- Sagan can talk. Somehow.
- Annie hides her immortality by getting a new hairstyle every few years. The show tells the audience that they have simply changed the actress. Eliza also pulls a similar trick

and finally some other misc. scraps that weren't covered above:
-annie has some kind of "super" or "powered up" form, in which she seems to fuse with sagan. it can be seen on her move concept sheet, in the end of robo-fortune's story mode, and as a very tiny feature on one of robo-fortune's merch posters, but to my knowlege it's never really been talked about.
-she's been depicted with an "incognito outfit", presumably for going out in public and not being recognized by fans.
-sagan is named after renowned astrophysicist carl sagan. this isnt really relevant to anything but it's not on the wiki so i figured i'd share :b
- and this random pic of annie in the past with a different look, plus gun and minus eyepatch, apparently official art from the "digital art compendium". i haven't seen the source for this one myself though, and count this one more as speculative canon since that ingame image up there with her eye uncovered doesn't show a scar or any kind of damage from this.
-another canon fact about annie is she is strong and brave and i love her.

she can still only normally see from the one eye in her head [and likewise probably has terrible depth perception lmao], but she can “project” her vision into the one sagan has if need be, during which time both he and her main eye are blind.
even though sagan’s vision is his own and she doesn’t actively “see” through that eye most of the time, the stuff he sees still becomes part of her memory and she can recall it if need be, though it’s far less tangible and kind of a surreal experience trying to do so.

the space where her other eye was is now just...space. like empty starry void stuff. yes, TECHNICALLY, you could put stuff in it but why would you. sagan can feel when something interacts with it and it’s really just weird and uncomfortable for both of them.

annie doesn't actually need a weapon and can channel her powers naturally through her body, though doing so may take a bit of concentration depnding on the kind of attack or effect she's going for. the cleaver acts mainly as a conductor and enhancer for this energy; making it easier to draw out, release, and shape along its swings.
as sagan is the source of their powers, the strength of her abilities is slightly dependent on her distance from him. something like long sustained flight is really only capable if they’re touching, but she still has ample firepower and ability to zip around for a pretty good range otherwise.

Not interested in anime

absolutely hates being called her full name; hasn't gone by anything other than "Annie" for longer than anyone that should be alive today should know.

part of her curse of eternal youth is remembering everything up until the point it kicked in and she stopped aging [i.e. when she was Actually a kid] exactly as well as if she hadn’t aged.
from that point however, a lot of it is hazy as shit aside from more recent times [as you’d expect from someone who’s been around hundreds of years].

also hates being restrained. her fighting style is very kinetic and relies heavily on mobility/having space to execute it; take that away and you get one very uncomfortable and very angry starchild. [this one's 'cause of y'all with the damn handcuffs asks. this is part of why she was so agitated during the arc]

what's in the pouch? whatever is narratively convienient. is it snacks? is it a quick incognito disguise? is it her whole entire sword? who knows. i think it might be infinite hammerspace in there.

despite being generally aloof and not wanting to get too involved with or close to other people most of the time, she does have something of a soft spot for fellow parasite hosts. with as much as sagan's helped her through the ages[and vice versa], she knows the stigma against them is unwarranted, and feels obligated to kind and understanding to them where society won't.

i haven't put much though into this side of her story yet, but i've decided part of the mythos of the "annie of the stars" character as a figure of legend is that she literally lives, among the stars.
if there's enough folktales about her to base an entire show off of, i'm willing to bet she used to be less elusive when she was just about fighting skullgirls before dedicating herself to the whole "looking for the underlying source" thing.

there's not a overarching plot to this thing at all, but geez, we kinda got some history here, huh?

taught sagan to say fuck [and other swears, in her stead]. he used to have to do it on command but he's gotten really good at filling in for her.

has a stoat fursona that beo helped her make. she thinks it's neat/cute but has no real attachment to it.

attempted to sue the crystal gems for ripping off her entire shtick [it didn't go well]

beowulf also taught her how to dab.

@sparkeletran is a nuisance and must be stopped

the 70$ pile of high school musical merch. sagan and beo both wear the t-shirts sometimes. she hates it. don't let her attitude fool you though this is actually the best and most important ongoing joke in this whole damn thing.

the first handcuffs stint. they’re gone now but they had a good ~30-post run, and she did take to learning lockpicking because of it.

this.

hey. guess fucking what lads. handcuffs ROUND TWO 'cause y'all just don't fuckin' quit. the first mini story arc sorta thing, in which she visits the cirque des cartes and has an aggravting encounter with taliesin. [ON HIATUS i got burned out as hell on it]

[[redacted for ""spoilers""]] due to said encounter with taliesin

sparkeletran is a nuisance,

"the official annie of the stars instagram is just cat memes but with sagan" it's canon but i haven't decided whether it's something she would have had already or a recent thing. [either way, hasn't been touched on yet due to the arc taking so long]

badart annie is sorta like her own thing at this point but nothing that happens with her is canon; she p much just shows up for exceptionally dumb posts. we did give her noclip though which is terrifying.
on that note i may as well include the things that are Not canon but y'all won't let me forget

beo's animated belt thing. look. it doesnt talk.

spray-on boots.

the lawnmower weapon

uhhhhhhhhhhhhhhhhhhhhh homestuck

credits are also going here since there's not a great place to put them otherwise
snazzy animated skullgirls logo by hanaxsongs
character icon set by tristepinguino
page theme is Re:volutuion by glenthemes [already linked down there in the corner but yknow.]
all other [non-ingame] arts by me hell yeah bro

SERVER CANON

goes here for now because i'm having trouble editing the theme rn hoogh.

beowulf actually has 3 parasites and is completely unaware of any of them.
--▫the wolf cloak, which saps one's intelligence in return for fighting prowess.
--▫the Hurting
--▫grendel's arm, a remote parasite [...]
we haven't figured all of it out just yet.

scythana is beowulf's daughter [FUCK what canon said i'm on this boat now too]

concept art twink beowulf is his son who also loves the dumb wolf aesthetic and takes it too seriously.

skullgirl with a BAT.

unstoppable

Sagan's canon information and characterization is basically nonexistant, so i got to do pretty much whatever i wanted with him lmao.

simply put, he's a little gremlin of a partner, but he is genuinely good-natured and a happy-go-luckly little dude. mischevious, loves to get up to Shenanigans, go off and hide/disappear to fuck knows where for several hours, climb and sit on tall things[or failing that, annie's head], etc. @sawkinator has described him, regrettably accurately, as "the Token Disney Animal Sidekick". he has a lot of mannerisms like an animal, but is still very much a being of at least average human intelligence.
he's also surprisingly indestructible. far from invincible of course, but in canon he's been shown to be quite stretchy and...possibly have minor shapeshifting capabilities?? he's pretty much immune to being squashed and feels very little [if any] pain from most things.
really, as far as i can tell he's pretty much a weird sentient plushie. like, if it's not going to damage a plushie, it's not going to hurt him; examples being: getting knocked back really hard or falling a long way? not a problem. fire? problem.

Sagan tends to be somewhat nonverbal and generally only uses a few words or short phrase at a time when he does speak, which sounds something like the voice clip below. that being how it is, he can be kind of inscrutable and more than a bit jarring to most people--though at this point annie's been with him more than long enough to be completely desensitized to it and doesnt quite get why anyone would be perturbed. fortunately, with that familiarity also comes understanding, and she can easily "translate" and articulate more of what he means from his expressions for other people.
this understanding is a two-way street, and on its other side is sagan's sensitivity to her moods. annie's not particularly...communicative of her emotions, but sagan can always tell when something's bothering her or she's having an off day [...perhaps sometimes even before she herself does], and is far better than anyone at helping her feel better.
all things said and quirky antics aside, he and annie are exceptionally close and fiercely protective of eachother the moment it comes to it. they don't make a big deal of showing it outwardly, but they know they've always got eachother's backs.

he's taken quite a liking to beowulf as well, and beo defintiely shamelessly enables sagan's shenanigans.
as i see it, annie may be the passion and power of their team, but sagan is the heart and soul. beowulf is like....comic releif and emotional support. not entirely necessary, but certainly welcomed to have around.
yeah.
listen im a big sap i just want them all to be good friends ok. i love them.

also sagan does like and watch a lot of anime.