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Ok!! headcanon hours!!!!
 
First of all, Chrysalis and Tirek are pretty much Cozy’s adoptive parents in this universe, enough with “bickering friends forced to work together” they’re FAMILY don’t change my mind
 
Cozy Glow was born to a family of very talented unicorns (shown in first pic), their professions revolved around performing incredible displays of magic to crowds, they’d honed their skills in prestigious unicorn schools and planned for all their kids to do the same and one day join them in their shows
 
There may have been some very distant pegasus in their family but the chances of having a non-unicorn child between two unicorn parents were pretty slim- oh
 
Cozy glow’s name had been picked out before she’d been born, it had been a fitting unicorn name, symbolizing the glow that comes from a unicorn’s horn, a unicorn, who goes to magic school and gets a cutie mark in magic and performs magic shows so when Cozy was born a pegasus they were, how do you say, Upset
 
Cozy’s parents quite frankly didn’t want to deal with her, wanting to pretend she didn’t exist at all, often finding reasons to leave her behind when they went to gatherings and when she was old enough sending her to boarding schools and camps, a lot of people were surprised to hear they even had a daughter if they got the chance to meet her
 
Cozy ended up acting out a lot to get attention from older ponies, and her mischief getting more and more serious and planned out, every time her parents were called they were zero help, sometimes the address they’d written down was to a donut shop in Saddle Arabia
 
Until finally she was sent to Twilight’s school and well all that happens, Cozy relates to Tirek hating his family a lot and thinks the idea of taking the magic from every pony in Equestria and using it for yourself is pretty cool too
 
Twilight and the gang tried to contact her parents but turns out this was one of those donut shop times, with pressure from Equestria to do something about the pony who tried to tried to steal all the magic in Equestria the decision was Tartarus, only temporarily, to figure something out..
 
When Grogar brings everyone back and they’re forced to work together Cozy gets what she feels like is the only family who wasn’t Awful to her, even if it’s made up of some of the worst villains in Equestria
 
Even Chrysalis and Tirek have to admit the whole sending a literal child to pony hell thing was messed up, but generally treat her as they would any other villain they’re working with, but while they’d deny it, they can’t help but care a little for the filly (”Uhm Cozy, you are NOT reigning evil upon Equestria without a jacket”) and maybe they spend more time then necessary at the local carnival “researching” because lookit her she’s so happy
 
Cozy actually feels sorta cared about for once, and totally ready to reign evil upon Equestria, until……..
 
So yea
 
It doesn’t last long, for Cozy at least, Twilight, the new ruler of Equestria sees the statue in the garden and can’t stand the sight of a scared little filly turned to stone, so unfreezes only her, hoping to set her on the path of redemption, Twilight knows her parents aren’t showing up anytime soon and asks to take care of the filly, maybe raise her as her own
 
Cozy’s pretty much like “fuck off” (but in child friendly old timey words like golly gee), she does accept her offer because she doesn’t want to be turned to stone again (not that Twilight really wanted to like, do that) but is incredibly resentful towards Twilight (and everyone pretty much), who turned her favorite people to stone and were planning to keep her in Tartarus, even if Twilight says it was only temporarily, Cozy doesn’t really believe her, but it’s still better then nothing
 
While Twilight’s very nice to her Cozy just has a very hard time trusting her, especially when Twilight doesn’t have as much time for her as she’d like considering princess duties and everything and Cozy gets passed around the main cast a lot, reminding her all too much of how her parents were always trying to get rid of her even if that’s not what was going on this time
 
(At this point im kindaaaaaaa thinking maybe she can get officially adopted by Starlight and Trixie and then really becomes happier but thats just an idea at this point, maybe for an alternate universe)
 
Anyways Cozy tries to be good but with a goal in mind, which is finding a way to free Chrysalis and Tirek, she’s not a unicorn, as we’ve firmly established, but Discord was freed by three arguing fillies so she thinks there has to be a way, she can’t let anyone know her plans because that could jeopardize everything but she dedicates all her free time to researching how to free them and is still looking for a way well into adulthood (context of last pic)
 
Also thinking of some other stuff like her reuniting with her brother (and being super pissed at him, even tho he was just a kid at the time too) buuuuut im getting tired of writing this so