Recommendations

A bitter love story depicting the realities of love between a female college students who earn money as a stand-in girlfriend, and men attracted to them.

~~ Adapted from the manga "Ashita, Watashi wa Dareka no Kanojo"

Both dramas have a historical setting and a very flirty, somewhat naughty ML. The main couple is either related (possibly half?-uncle and niece) or the FL believes they are (siblings).

It continues the story.
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Let me tell you with novel pov :
-Both has FL time-travelling to the period where our story starts. Both can't go back to their respective bodies as original soul of the bodies are already died and only soul of FL is survive by time-travelling through our story' main character.
-Both ML served for King of their period and they both have aristocratic family background.
-For FL, both are model student in their respective major, and undoubtedly smart. Their Inquisitive and quirky personality gives headache to their partner yet this is the reason they get attract to our FL isn't it.
-As slow-burned romance should, things are not going well at first in both. But don't worry it's always in Male Chases Females First tag.
-With politic, romance, time-travelling and most importantly period piece with extra comedic spice. I hope you should try this two master pieces for yourself.

I rarely get SLS for 2fls but these 2 dramas are like that. both mls are in love with their friend who doesn't know it
one gets married and the other rushes to a marriage just so they're not lonely while never having courage to confess and win over the obv better man who is their friend

Both are of fantasy romance genre where the characters are entangled from their past lives, with someone cursed of immortality and someone leading them all to meet again in their present lives. These two shows also slowly reveal the past as you go through the series, showing hints of the historical setting to it.

Both series are about Y fangirls' love stories, while their passion around Boys' Love is strongly depicted.

This is the 2001 version of this drama. It can be found subbed on YouTube. The cast is older.
During the Tang Dynasty, two women are due to wed on the same day. En route to their new homes, a rain shower forces them both to seek shelter in a temple. Downpour over, Du Bing Yan and Li Yu Hu quickly set out again. Unbeknownst to the people lifting their carriages, each is delivering the wrong bride to the waiting grooms!

Through a series of trials and tribulations, the newly-paired couples grow to love each other. As they say, “it’s fine to get on the wrong bridal carriage so long as you don't marry the wrong person.”

Both dramas are about a modern day FL time traveling into history and unexpectedly falling in love with the ML who is a general.

Both are shorter length dramas in which a modern day FL travels back in history. Both MLs are in the military (general vs. soldier).

Both are mini dramas that are historical/fantasy genres. Both MLs are generals, the FLs are quirky, endearing, and have something unique about them (they aren't human vs. they're a time traveler), and both couples get married at the beginning of the series, then fall in love.

Both dramas have a modern day FL who time travels to the past and falls in love.
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Both dramas have a modern day FL who time travels to the past and finds herself marrying the ML who is cold and overbearing. The two slowly fall in love.

Both are shorter length dramas with a modern day FL who time travels to the past and finds herself marrying the ML. Both MLs have an off putting reputation (cold behavior vs. strange illness).

Both dramas involve a modern day/future FL who time travels to the past and marries the ML.
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