Honestly, if Rue actually becomes a better person, i dont think ill be that mad if she gets with the MC. NOW HOLD ON, LET ME EXPLAIN.
I would say she needs to be punished for her actions but that's already happening naturally throughout the story so i wont mention that. firstly, yes she does need to atone for what she's done and actually accept that it was wrong and most importantly DO SOMETHING ABOUT IT and not just apologize with words. those are the conditions for her redemtion.
now as to why i'd be ok with her having a redemption? its simple, because its not entirely her fault. the way she acts is much more a fault of bad parenting. Her grandpa allowing her to make the badge system is proof enough. her parents and family spoiled her and left actually raising her to another kid. what kind of horrible parent would do that???? im not suprised she turned out like this with how shes being treated. Yes i know her mom acted nice and everything, but she still didnt do anything to actually help Rue grow into a normal person at all. a parents job should be to raise a child with good morals and they completly failed at that. THEY DIDNT EVEN TRY! honetly i feel kinda bad her Rue. while yes Rue is still very at fault, im much more mad at her family for not seeing what was happening and doing something about it.
if i missed something feel free to yell at me, its been a while since i read this so i might've forgotten something.