Interesting question! I second @ahsaaful, both male leads in The Story of Ming Lan fit the description. Perhaps it is true that Japanese drama have a darker undertone, like you said, but I can't think of any dark& dirty male leads in them. The male leads that are remarkable in my eyes:
Ying Zheng in The King’s Woman is a bloody tyrant and brute who stops at nothing to get the girl he wants.
Feng Tian Yi in Novoland: The Castle in the Sky has nothing of the traditional loving hero with self-denial qualities. Yes, he is a romantic hero, but his love is all encompassing, he even tortures the female lead, literally inhales her and wishes to possess her.
Yan Xun in Princess Agents starts as a happy-go-lucky guy, but he changes by a sad turn of events into a dark and cunning personality who won’t let anything stand in his way. His only feelings are left for the female lead.
Mu Liu Bing in Moon River is rich, insanely popular, but inwardly cold, sly and revengeful. His love interest is precisely the opposite: sunny, frank, open, strong. The day they met he took an instant liking to her, soon calculating every step to make her his.
Yoo Jung in Cheese in the Trap lies and cheats to get the woman he wants, he’s seems such a sociopath it isn’t funny anymore.
Choi Yeong Do in Heirs has all the characteristics of a high-end trickster in getting close to a girl that highly irritates him. His feelings change into a one-sided love. Still he genuinely likes her. This drama is rather dull, but Kim Woo Bin outplays Lee Min Ho here.