The one drama that seem to resonate with some of the things you wrote above is the 2018 drama Clean with Passion for now.
The thing about is beinh a Kdrama, is probably the first thing, then the parts with ML being rich, FL being poor. She does clean his house and there is a looot of pink in it,
But some of it doesnt seem to stick, like the ML really not a playboy, but he does go to a lot of matseon or korean blind date that the primarily purpose is to find a wife. They knew each other as youngsters, but it was when they were in grade school not highschool. I dropped this drama but I do think ML's mother is still alive as well as his grandpa.
I don't know. Hahaha i guess i clung to the pink theme part, and zeroed in on this drama, there was just so much abundance of pink in this drama. Plus cleaning part...