2nd Male Lead is possessive/obsessive asshole trying to stop lead's budding relationship

Th 2nd male lead loves the female lead and goes out of his way to stop her relationship from developing with the male lead. She's close to him, but hates what he becomes. The male lead and female lead end up together and the 2nd male lead gets what he deserves from being so shitty.

 fanitha:

Delightful girl Chun Hyang

Seen it, but thanks anyway.