Secret female lead has un-intentionally hurt main male lead, by pretending to be the driver of a vehicle that killed the woman he loved. Female lead takes the fall for her then fiancé (2nd male lead). Female leads existence causes continued hurt and conflict to main male lead and he devises ways to make her suffer, along the way her fiancé abandons her and basically becomes a monster of a human for the lengths he goes to, to ensure his own success. Very drama heavy, but once the connection establishes between the main leads, the romance feels really genuine and strong.
If you're looking for something lighter/comedic to watch
Lets Eat. Female lead accuses male lead of being a serial killer causing conflict between them. She is awkward around him, and it takes awhile for male lead to realize he likes her. There is also a 2nd male lead, her boss who is really cute. He has one sided love on her, but right now he wants revenge on her so causes her conflict through work because he hasn't owned up to his feelings. This drama, is really something different, light watching but has good pace to the story.
You could also try, just friend dramas where they don't admit their feelings until later, like 9 End 2 Outs.
