P.s I like this a lot for a setting but there are so many questions that got skipped over that dont make sense.
What happened to the girl who's body she is in? Hopefully she wasn't just erased! Did she swap with her? That would suck for her lol. Dumped into a woman with a shit job in a world she knows nothing of.. Or is this one of those 'its all in her mind' things? And in the end she wakes up? Thats even worse because it would all be for nothing!
Her friend realizes she has changed a lot- but shouldnt it be clear she is a totally different person? She should have zero memories of Taylors past beyond some basic stuff the game said, and it would be obvious to anyone who knows her right? She also would have little common knowledge of this world - beyond what was in the game too.
She is meant to be the best student, but now some random office worker has replaced her- who presumably would lack all the lessons Taylor has learned at school- no way a royal fantasy academy has common lessons with modern Japan- so how is she gonna not fail at all her lessons?
Maybe some or all of them get answered soon? Not that it hugely matters even if it doesn't bother with the finer points, I can still love the setting and characters and story for what it is.
pretty much everything you've said gets answered later.
The deal with Rei's body is shes basically the same person as the regular MC, as shown by having the same first name as her past life since in the Otome game you have to enter a name for your character. She basically awakened all her old memories of her past life when she heard Claire's voice and saw her.
The deal with Misha is Rei still has all the memories of her current life, just her old life got lumped in, so she's able to maintain the same dynamic with Misha aside from openly lusting for Claire. This is a spoiler though so if you must know, and I warn you this is a spoiler, Misha does eventually figure out that Rei is no longer the exact same person as her childhood friend. Also on an unrelated note I dunno why the manga is saying Misha's last name is Ortho, when that seems closer to another character's last name of Orso, and the web novel had her last name as Yule.
Rei only got into the academy as the best student out of all the commoners because of her magic ability, the character of Rei herself doesnt know anything about things like culture and etiquette that the school teaches as extra for the nobility. As another further spoiler though, and this might ruin the impact of a later chapter if you read this, basically Rei is a super fan of the entire setting and franchise, to the point shes read up on all the lore and history of the world and actually knows more than the average student should. Also the series comments on how theres a lot of overlap with modern Japan since its a game made by Japanese devs.
Sorry for the dump of spoilers, but I didn't really spoil any major plot points in this so dont worry if you saw what you worry might ruin things, it doesnt.