Ms. Temper & Nam Jung-Gi, Chief Kim..... that's all I can think of.
If you are looking for a Korean Drama without much romance..... good luck with that. It's like finding a needle in a haystack. Japanese Dramas are much better at making very silly, lighthearted comedy shows without a big emphasis on melo/romance.
However there are lots of Crime/Thriller dramas without romance if that's your thing.