I think she did it more for herself. she was under pressure from the bank and the loanshark everyday and night with no hope. couldn't sleep for a long time.
that's how her dickhead boyfriend could convince her to go ask MC for help using his feelings and her body. she was desperate.
if you choose the dark path in chapter 1, she didn't want to go back to MC to ask for more help because he hurt her deeply. if he raped her for 20k, you can't imagine what he would do for 100k. though after the fact, she realized she loved him before he blackmailed her.
on the "nice" path, she seeks forgiveness though, and promise that she will prove that she is really sorry if MC doesn't forgive her. so she does think she deserves to be forgiven. but she doesn't think she deserves to be loved and doesn't want to risk losing MC if the relationship fails.
her choices are rather irrational for me, but I don't dislike her. she is not a bad character at all. I don't get the anti Nicki protest here
dev said she is not, but the guy that did the character guide wanted her to be so he bumped her up to the main LI category
it could be said that Carolina and Risa are two sides of the same coin. one is too stuck up, and the other too irresponsible. put together, you got a perfect mix
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you forgot the fact that Risa is adopted by a rich family that only wanted a puppet, that she is utter disappointment and disgrace to them, that everything she does is scrutinized to the extreme... and she can still stay playful and positive everyday (though drugs help a lot there). that adds several layers to the character.