Please Recommend Dark Romance Kdramas!

Hello everyone, recently I watched Miss Panda and Mr. Hedgehog and I really loved it. 

I also watched Oh My Ghost and one of the things that I loved about them most was that the last few episodes got a bit dark.

I don't wish to spoil anything for those who haven't seen them yet, but I can tell you that stuff goes downhill fast.

I'm looking for another Kdrama or movie like that. 

If you have any recommendations, please send them my way! 

Thanks!