Isekai'd as a side character

“This is your wife. She is yours. Play with her until you get bored.”
“Mother-in-law, is that really something you should be saying to your barely 10 year old child?” my young husband stutters. He has a face with scales on it, hands with scars on them. I worked hard to look after my husband who looked like that.
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Orianna dies in an accident and is reincarnated as a villainess pursued by the antagonist in a novel.
To evade her tragic fate, she resolves to change her ways and establish herself as a distinguished lady in high society. However, despite her transformation, Orianna is betrayed by her fiancé and framed for conspiracy. Her unexpected savior from this dire situation is none other than her nemesis.
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○ : SA
○ She’s a villain in OG but not THE villain of OG

She became the wife of a male lead inside the novel that she couldn’t finish. She was also the supporting character who died out of jealousy of the relationship between the male lead and the heroine. Daisy, who didn’t want to face such a dark future, came up with a condition instead of marrying the male lead, Carlyx. “Please divorce me in two years.”
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○ : miscarriage
○ A warning that this isn’t really a romance in the end

Although there are some downsides of being the sister of an antagonist, in the end, does it even matter? After all, I'm still fated to be the family heir at the end of the day.
But things take a turn for worse, and my life goal to reach the top is jeopardized by my back-stabbing little sister. There's two weeks until my father returns. During that time, I must somehow find the best groom of the empire.
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Rosa remembers her past life. She remembers reading about the Helios Empire in a novel before dying. When she arrives and meets her biological father, her life is turned upside down once again as she’s forced to live the life of Rozenta Estella, the sole heir to the Estella estate and the only son of the Duke of Estella. Rozenta is a supporting character in the novel, but there was no twist like this in the original story.
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When the clock strikes midnight, I regain memories from my past life and realize that I am in a story. The problem is that the story is a tragedy. The male lead is an insane bastard with a streak of madness and my sister is doomed to be a mental wreck due to his obsession, facing a tragic ending where she loses her mind. I absolutely cannot let my beautiful and kind older sister meet such a miserable fate.
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○ : rape in sorta-flashback, alcoholism, abusive parent