Like, an FL who's already dated around, sexually experienced, had relationships, etc., isn't ashamed of it and the show treats it as fine and cool. Would especially love CDramas with this! (Doesn't count if it's just one prior attachment to a doomed love or whatever.)

I wasn't sure if you meant "one prior attachment to a doomed love" as just meaning a non-sexual relationship or not, so these are one relationship, but it was clearly a sexual one.

  • His and Her Secrets (FL is older than the ML and married at the beginning. It could be assumed she had other relationships prior to that and there was an unfounded rumor about her being involved with her professor at school)
  • Lost Track of Time (FL marries and is pregnant twice by the SML and then marries him again after her time travel do-over but ultimately ends up with the ML)
  • Renascence (FL marries and is pregnant by the SML before the bodyswap, she ultimately marries and has a son with the ML)
  • The Best Friend (FL is married and then he cheats on her and leaves her for her best friend, and she ends up with the SML)

And not Chinese but...

  • Pachinko (FL has a relationship with the ML and gets pregnant, then marries the SML and has a second child by him)
 emeraldarrows:

I wasn't sure if you meant "one prior attachment to a doomed love" as just meaning a non-sexual relationship or not, so these are one relationship, but it was clearly a sexual one.

  • His and Her Secrets (FL is older than the ML and married at the beginning. It could be assumed she had other relationships prior to that and there was an unfounded rumor about her being involved with her professor at school)
  • Lost Track of Time (FL marries and is pregnant twice by the SML and then marries him again after her time travel do-over but ultimately ends up with the ML)
  • Renascence (FL marries and is pregnant by the SML before the bodyswap, she ultimately marries and has a son with the ML)
  • The Best Friend (FL is married and then he cheats on her and leaves her for her best friend, and she ends up with the SML)

And not Chinese but...

  • Pachinko (FL has a relationship with the ML and gets pregnant, then marries the SML and has a second child by him)

Oh, thank you for so many recs! I will check them out and see how they land. One prior relationship could be okay - ideally I would love a lady who's explicitly slept around a lot and enjoyed herself doing it (I know it's a tall order for a cdrama), but in general I do just want to get away from the omnipresent trope of the FL who's innocent/naive about love, even if she's older or mature in other ways. So thanks!!

 octopus_joy:
One prior relationship could be okay - ideally I would love a lady who's explicitly slept around a lot and enjoyed herself doing it (I know it's a tall order for a cdrama), but in general I do just want to get away from the omnipresent trope of the FL who's innocent/naive about love, even if she's older or mature in other ways.

Unfortunatley I can't think of any dramas that I could confidently say are probably what you're ideally looking / hoping for. But I've listed a bunch of romance dramas that might fit the broader scope of a FL who isn't completely naive and innocent when it comes to love. 

 octopus_joy:
Like, an FL who's already dated around, sexually experienced, had relationships, etc., isn't ashamed of it and the show treats it as fine and cool.
  • +1 Love to Hate You - The FL has dated many, many men and slept with a lot of them. The dynamic is a bit odd though. They frame it as her mostly using her skills to punish men who were cheaters or abusive. The drama tries hard to be cool about her history. Sometimes it succeeds and sometimes it doesn't. 
  • Search: WWW - The FL sleeps with the ML the day they meet (the vibes were right). He wanted to start a relationship and she wanted to move on and leave it as a one-night stand. iirc it's implied that she has experience dating and I think her ex might have been a recurring character (but I don't remember the details).
  • Jealousy Incarnate - At one point in the story, the FL openly dates the ML and the SML simultaneously because she is torn between them
 octopus_joy:
Would especially love CDramas with this!
  • Zhang Gong Zhu Zai Shang - The FL keeps a harem of handsome bodyguards, it's implied that she's experienced, and she is very confident in terms of flirting and taking the lead in romance and beyond.

In these noona romances, the FL dates / is married / gets back with her ex while the ML is in love with her and there is a strong implication that the FL is getting with the wrong guy(s) and not having a good time of it while "Mr. Right" is hiding in plain sight right under her nose:

The FL had a relationship with another man and got preganant by him but she is forced, in one sense or another, to marry the ML, who she ends up falling for:

The FL only has one confirmed crappy prior relationship:

Ah, well, in that case, possibly Secrets of the Shadow Sect - FL has a harem of men and it's implied/believed that she's involved with all of them (she does ultimately only end up with the ML).

 emeraldarrows:

Ah, well, in that case, possibly Secrets of the Shadow Sect - FL has a harem of men and it's implied/believed that she's involved with all of them (she does ultimately only end up with the ML).

Oh, thank you! A harem of men does sound great. I appreciate it!!

@AH, it won't let me quote you (because your post is too long and too full of recommendations!!) but thank you so much! That's a ton of shows to look into, and I really appreciate all of the detailed comments. I did know that the ideal of someone who was happily slutty was not likely to get results, but I am definitely excited to have so many recommendations. Thank you again!!

 octopus_joy:
Thank you again!!

You're welcome! I hope you find something that hits the spot :)