Dr. Gang (2006)

Dr. Gang and Lovers both have gangsters and female leads who are doctors. Somehow the male leads also look similar and their characters are loveable and romantic.

MLs always protect and lookout for the FL. Both have ties to the Korean mafia, but wanted to go in a more civilized and non-criminal direction in life. At one part of the drama MLs are wanted for murder. Romance is similar.

Both are medical dramas in which the main character is a doctor and gangsters/criminals
Both have rich female leads