So, what Im looking for is something with a relatively normal male mc who ends up getting caught up in something big or dark, or seedy underbelly of the city,  or etc. type of thing due to the female lead.  I would prefer that the male lead was not already a part of this type of world/thing before he gets pulled into it IE:  Yong Pal doesn't fit this rec because Yong Pal was already involved by treating gangsters and mobsters in..less than ethical conditions.

Romance is a huge plus, any genre or setting is ok, also any time period is ok as well (historical drama's are fine)

Thank you for any time spent reading this

  • Ms. Perfect - both the normal ML and the normal SML get pulled into a series of events that are dark and insane because of their connections to the main women in the story
  • While You Were Sleeping - due to an encounter with the FL, the ML (a prosecutor) begins to be able to see the future in his dreams; he gets involved in trying to prevent tragedies and helping the FL solve a murder case because of the FL

A bit further from what you're looking for, but also possibly worth checking out:

  • Dream High - the FL convinces one of the main male characters to leave his simple life in the countryside to attend a high school in the city for students who want to be performers, and he ends up going through a complicated journey
  • I Hear Your Voice - when the leads are both kids, the ML's father is murdered (so in that sense he's already involved in something dark and isn't completely normal) and the FL helps him by testifying against the murderer in court; the ML could've left it at that (he was just a kid), but he promises to always protect the FL, and when the murderer is released years later, the ML becomes involved in a series of complicated and violent events due to his promise
  • Misty (still airing) - the ML was a prosecutor from a very well-off family (generations of supreme court judges); he fell for the FL, an intrepid reporter from a poor family, and married her even though she was clear that she did not love him; he left the prosecutors' office to become a defense attorney due to corruption in the office (he has his own principles); this is where the story begins; when individuals from the FL's past re-enter her life, the ML gets involved in a dark and complicated series of events including a murder investigation and a fight to bring down major corrupt officials 

Edit: also since Hwayugi / A Korean Odyssey is in your PTW list, I'll mention that the ML in that one is a deity at the beginning of the story (so not a regular person) but he does get dragged into a different role with more responsibility and darker consequences largely because of the FL

Puck! (Drama Special) - to payback his wife's debt, ML ends up working for the loan shark as a gang member & debt collector - you know the type you always see in kdramas that use threats & violence to collect their money

Others that are not exact of what you're asking for:

Drama Special Season 7: My Happy Home

Liar Game - 'Liar Game" is a sketchy, underground swindler type of game where participants are each given 100 million yen, and the aim of the game is to trick other opponents out of their hundred million yen. If you win, you keep the money, but if you lose you go hundred million yen into debt. FL is anonymously picked & forced into such game where she has no choice but to participate. When she loses the game she contacts ML, who's one of the best swindlers in town, to help her win it back to pay back the debt.  

There are 2 seasons + a movie; I've only seen the first season. There's also a Korean version which is slightly modified. I don't remember the plot details, but I think the FL was also used as bait to lure ML to participate in the game.

Meloholic - you can kind of say that his life took a turn because of a woman. There are 2 women. Fist one is the ex: had he not been at her place at the wrong time, he would had never obtained his special abilities. The second woman is his future girlfriend: because of her and her list of admirers he gets entangled with some stalkers. 

  • Spy Myung Wol - ML isnt necessarily an ordinary citizens cause his profession is being a star, but somehow he gets pulled into an espionage due to and somehow in connection to the FL. but there was maybe some parts of his involvement into the shady spy game due to his newly passion to find out about some dark history of his life
  • Capital Scandal - the ML is a spoiled playboy during the Japanese occupation of Korea. he has a good life since his parents are somehow doing business with the japanese, but he meets the FL who is a very patriotic woman who wants to delved into espionage. and the more he gets in contact with her, the more he gets into the rabbit hole of espionage
  • Age of Youth (season 1 and 2) - the male characters are totally normal but somehow gets put into secret investigation due to the female leads, though this one it doesn't really go into the underbelly of the dark reality of the city

my beautiful bride .. an excellent drama by ocn .. amazing plot   , you should check it out ..
bonus: awesome OST

Uh, do dramas where "normal" ML get pulled into a "dating" relationship with a famous FL count? (fake dating to avoid another man, scandal, etc)

I remember 1 Kdrama like that. Forgot the name though.

 Antonin:

Uh, do dramas where "normal" ML get pulled into a "dating" relationship with a famous FL count? (fake dating to avoid another man, scandal, etc)

I remember 1 Kdrama like that. Forgot the name though.

Yes that would be fine as long as the "normal" male lead has to deal with a different sort of world (like the way people would start treating him since he's dating a famous fl).   From what little you've said, it sounds like you're probably talking about That Fool which is aGREAT drama, and I really like it alot

 Robert:

Yes that would be fine as long as the "normal" male lead has to deal with a different sort of world (like the way people would start treating him since he's dating a famous fl).   From what little you've said, it sounds like you're probably talking about That Fool which is aGREAT drama, and I really like it alot

Yes, it's that one (I think xD) Thank you!

 Robert:
Uh, do dramas where "normal" ML get pulled into a "dating" relationship with a famous FL count? (fake dating to avoid another man, scandal, etc)

I remember 1 Kdrama like that. Forgot the name though.

Yes that would be fine as long as the "normal" male lead has to deal with a different sort of world (like the way people would start treating him since he's dating a famous fl).

This makes me think you might enjoy Queen In Hyun's Man or You Who Came From the Stars. In QIHM, the ML time travels from the ancient past to the present. He's thrown into a different world in that sense, and it's not the FL's fault, but the FL is the first person he meets who helps him navigate the world, and she's a celebrity so he also has to figure out how to deal with modern celebrity culture. In YWCFS, the ML is a several hundred year old alien (so not normal) but he lives as a rich and reclusive but otherwise semi-normal professor. Then he meets the FL, a famous actress living next door to him, and he gets dragged into the celebrity world as her sort-of manager.

You might also like the Master's Sun. The ML isn't 100% normal (he's the head of a mall group and survived a traumatic event many years ago that still affects him), but he can't see ghosts. The FL can, except when she's touching the ML, so she uses him as a "shield" and he gets dragged into her world of constantly dealing with ghosts. 

^ Thanks AH, always  good recommendations

 Antonin:

^ Thanks AH, always  good recommendations

Antonin, this reply made my day. Thank you!