Isekai'd as a side character

In the reborn world, the Crown Princess is voted for. I'm a very normal extra, so it's nothing to do with me. But why did I become a candidate for the Crown Princess?
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Oh Mari is reincarnated into the novel “My Dorothea” as the heroine's best friend, Maristella. Aware that the heroine, Dorothea, ends up betraying Maristella, leading to the execution of the latter, she vows to do her utmost to survive and live her new life to the fullest.
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I spent a carefree day lounging about after paying off my tuition loans, but ended waking up inside a novel as the Amel, the only daughter of a poor count. Even if I worked for the rest of my life, the debt my family accumulated is too much for me to even be able to pay off. Not only that, but it seems that I ended up having a one-night experience with Kyle, the male lead, after getting stupid drunk...
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○ : sex w/ one party drunk

Wishing for a new life, Asili Rosé was reborn as a princess in a novel she once read. She thought she was born with a golden spoon, but it was actually just a gilded spoon?
Once she realized that nothing but ruin awaited, she found a diary foreshadowing the future...
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○ : suicide; torture; PTSD

Somehow, before the appearance of the female lead, I became the male lead’s wife. Since things had already turned out this way, I decided to try my very best. But what will I do when the heroine inevitably comes?
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○ Though referred to as a villainess, the original Dylan was just a very sleezy side character
○ : stillbirth (mentioned); maternal death (mentioned)

My favorite secondary male lead, Kaelus, died. Living in poverty without him, I eventually became ill and died as well. I thought I would return to reality, but I went back in time instead.
This means I have to save my beloved, right?
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