Yandere males obsessed with the main girl?

By obsessed, I assume you want the jealousy and angst due to it... Not much of that in in K-dramas...Maybe:
--- Que Sera Sera

Tons of it in C-dramas (but u don't want historical):
--- Sealed with a Kiss ... He defines the Obsessed Male!
--- Too Late to Say I Love You .... Very obsessed, not a perfect hero,passionate love.
--- Loving, Never Forgetting ... well, she was obsessed, but he acted on it, he was jealous, possessive.

T-drama:
--- Meteor Garden ... Taiwanese BOF / HYD .... Ultimate obsessed Male!!! ...Possessive, passionate,  with all the jealousy, angst, etc...

Summer's desire- two yandere guys obsessed with the lead girl

Bridal mask- the villain guy is the definition of psychopath

Falling For Innocence- the second lead is a yandere

Roy Leh Sanae Rai- the ML is a anti hero type

The thousand years of love- the villain guy is yandere 

Delightful Girl - the second lead is a stalker

secret- the ML is a stalker

Love never dies- the villain vampire likes the lead girl 

Cruel romance- the villain is a stalker and a psycho

Memory lost- villain is a stalker

Ngao jai- obsessed villain

The journey- u might like it cause two guys obsessed with the girl