I love a mystery thriller drama that also has romance. The dramas that fall under this category and the ones I have ALREADY watched are: 

My Perfect Stranger 

Reset (chinese) (LOVED IT!)

Link Eat Love Kill (I LOVED THIS ONE, WENT INTO A SLUMP AFTER THIS)

Abyss

Strong woman do bong soon

Catch the ghost

Repeat the year (the romance was very little, I would prefer more romance)

Sisyphus the myth

Flower of evil

Happiness

Bulgasal

Come and Hug Me

Watashitachi wa Douka Shiteiru 

Watashi no Tadashi Oniichan 

The Game: Towards Zero

He Is Psychometric 

No Secrets (remake of I Hear Your Voice and even better, imo)

I Hear Your Voice  

The Ghost Bride

Chains of Heart

and maybe 

Island 

The First Responders

Sell Your Haunted House (the lead's relationship could be seen as platonic close friends or romantic, I saw it as romance, personally)

 emeraldarrows:

Come and Hug Me

Watashitachi wa Douka Shiteiru 

Watashi no Tadashi Oniichan 

The Game: Towards Zero

He Is Psychometric 

No Secrets (remake of I Hear Your Voice and even better, imo)

I Hear Your Voice  

The Ghost Bride

Chains of Heart

and maybe 

Island 

The First Responders

Sell Your Haunted House (the lead's relationship could be seen as platonic close friends or romantic, I saw it as romance, personally)

Is there actually romance in Game Towards Zero? Because in the Genres it doesnt mention romance

 

 Spring Flower:

Is there actually romance in Game Towards Zero? Because in the Genres it doesnt mention romance

 

Yes, definitely. It's slow burn at first but the leads fall in love partway through,  sleep together after ML recovers from nearly dying, and the last scene shows they stay together until the end of their lives so it's safe to assume they get married.

Is a happy ending required?

I hope this helps!!!

  • White you were sleeping
  • The Girl who sees smells
  • Bring it on ghost
  • Hello Monster
  • Find me in your memory

Also:

  • Mr. Sunshine
  • Bridal Mask
  • Love me If YOu dare
  • Time Between Dog and Wolf
  • When a Snail Falls in Love
  • Iris
  • Cruel City
  • City Hunter
  • Spy
  • My Name
  • W: Two Worlds

Thank you everyone for all the recs. I have watched some of the dramas you have suggested, such as Big Mouth, Tale of the Nine Tailed, My Name  Flower of Evil. But there are a lot of new recs. Thank you so much!