Both are fluffy dramas with a modern day FL entering a historical world and falling in love.
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Both are lighter, fluffy dramas with a modern/future FL in a historical setting.
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Modern day FL in historical setting, falling in love with ML.
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Both are short length dramas with a modern day FL finding herself in a fictional historical world where she's supposed to die early in the story.

Both are short length dramas with a modern day person entering a fictional story and trying to change it/stay alive inside that world.
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Both dramas are about a modern day FL accidentally entering a fictional historical world (drama vs. novel) and falling in love with the emperor ML.

Modern day/future FL enters fictional historical world.
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Both are short length dramas with a modern day FL entering a historical setting and falling in love with the royal ML.

Modern day FL enters historical setting and falls in love with royal ML who she is married to.
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Both are short length dramas with modern day FL entering a historical setting. Both MLs are royal.
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Modern day FL enters historical setting and finds love with the royal ML.
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Both are mini dramas with a modern day FL who time travels to the past and falls in love.
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