Based on what we know the plot seems interesting

So based on what we have so far. Our MC was probably the true owner of the body. And after 10 years of an imposter taking over the body the original Renee returned.
-> Handwriting and Behaviour of old Renee got regocnized by brother and childhood friends

For whatever reason a dragon possessed her and did all kinds of evil deeds.
-> murderer knight, whose family was cursed by dragons felt disgusted by her for 10 years, but not anymore - because before it was a dragon that cursed him inside of her but not anymore

But based on how the friend implied to not let her die THIS time and her being overly cautious of the cursed knight, there must also be time regression in the plot. Is that why MC probably believes she is in a novel? Even though it is probably her real life or first life?
-> confusion of the circumstances maybe can be explained by regression + forced body takeover by a dragon + original Renee being ejected out of the body forcefully

This looks like so much potential and I really hope the cursed knight is the ML cause he is so funny together with MC and I just love how everyone hates him despite him not having done anything to Renee in THIS timeline yet~ ٩(๑❛ᴗ❛๑)۶