Some I can from the top of my head are:
- my lovely sam soon (it's an older drama, but it does have a very strong female lead, the male lead at times reminded me of the lead of it's okay that's love', so I'm guessing that's what you're looking for.)
-healer (strong female lead, check. the dude is kind of a bad boy, in the sense that he's doing illegal shit and does what needs to be done to get paid (except for murder))
-secret garden (also strong female lead and male lead that at times acts like the one from 'it's okay that's love)
-our times (this is a movie, but still somewhat fits the premise you're looking for. the male lead is basically the definition of a 'bad boy'. the female lead is a little more sensitive, but she's still really likeable!)