The setting reminds me of Kind Goblin's bride. The male lead is a king/prince, the female lead is a bit of an innocent lady.

So both of them had a good seggs on their 1st night. Then, on the next day...the female lead went to male lead office and he asked her if she is ok and she mentioned that it kinda hurt down there. So he asked her to show him but she was embarassed and he asked whether she prefer a doctor to see it or him. She preferred him because he is the husband and she lifted her skirt. Then he mentioned that her🐱 is swollen and he started inspecting and sx18 stuff and they ended up banging on his table.

Sultan's Love?

edit: i know you said chinese/korean setting, but try it out lol

Idk never read it, but it might be Gwang-an (sorry links don't work for me)

I'm in idol hell T.T

Sounds like the sultan's flower