being spoiled, she just wanted her brother's love attention... Fine, I can accept that... What I can't though, is that she DID screw her brother over more than once acting this way...

but Marie isnt really spoiled tho, shes acting like a bitch because she wants her brothers attention (which honestly isnt the best method) which unfortunately led to MCs death. The parent wasnt exactly spoiling her either tho. Later the parent even went as far as leaving her to her own device which through sheer bad luck led her to kept meeting bad men that leave her in huge debt. Even after being reincarnated, her bad luck remain with her parent leaving her with huge debt and even more later once she proclaimed herself as the saint. And dont forget the fact that shes stuck with these goddamn power rangers whose nothing more than god of pestilence.

that isnt nao or raph.
and the whole Bitch being the cause of the waves and every single bad thing ever because she was a god was also pretty shitty writing.
at least this story is giving everyone a chance at redemption and character development.

they find out they are each others brother and sister

Leon bets a shit ton of money

Let's just say the bet A LOT of money.