Isekai'd as a side character

The body she inhabited after entering the world of book was, unfortunately, a member of a species that reigns as the evil of the world, Karina Apocolypta. However, in the original work, the novel’s plot begins to twist as she saves the life of Reneiger, the first love of the female protagonist.
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○ : child abuse

Imagine being reincarnated as a minor novel character who will meet a pitiful end early on. With nothing to lose, Adelia makes the perilous journey to become the empire’s first white mage in 300 years in order to have the crown prince marry her so she can have the power to get revenge on her abusive family. And once she becomes a member of the imperial family, Adelia can live happily receiving the love of her favorite character.
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○ : child abuse

I possessed an extra who died as soon as the original work started. I was the hero’s incompetent guide. Only until I die, will the male lead meet his new guide, the heroine. To safely stray from the original work, I pretended to be dead after consuming a toxic flower that throws you into a coma, but…
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I possessed the body of Tiarozety Isol, a supporting character in “The Opponent of the Dragon.” The book will send me back to my world as soon as I complete the ending of the male lead, Lexion. The problem is I’ve never read this book before. Besides…
“Penalty?”
“Yes.”
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○ : abuse; kidnapping

A former call center employee finds herself transported into a fantasy novel, where she becomes the “servant” of the male protagonist, a cruel tyrant who kills anyone he doesn’t like and lives in lust. She doesn’t want to die like the original character, so she plans to escape before the tyrant finds the female protagonist.
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A romance fantasy novel in which a runaway female protagonist, Yeoju, suffers from amnesia. In that novel, she possesses Seina, the next door neighbor of Yeoju. But why do male lead candidates keep showing interest in Seina?
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When I opened my eyes, I found myself about to be sold in an auction. The novel’s male lead burst in and saved me, but all of a sudden…
“Please be my wife and show this empire your worst behavior, so wicked that no one would dare to approach me when they see you.”
“What's in it for me?”
“I'll give you ten billion.”
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○ : human trafficking
○ She is an villain but not the OG antagonist

It's easy to overlook the extras in a novel, but when one avid reader wakes up in the body of "extra" Princess Lyla, she’s ready to shed the side character role and step into her mightiest form. Armed with hidden magic more potent than the empire has ever seen, Lyla is ditching the palace in favor of a nobler mission—protecting her bias at all costs.
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When she finds herself as an orphan in a novel she once read, Ronaldine decides to use her knowledge from her world to become an amazing secretary. Little did she know that her skills would take her all the way to the royal palace—where she becomes the tyrant emperor's personal secretary.
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