Golden Empire Two Weeks
Friends, both the drama and movie. It's not really similar to the ones you've written butvit is dark as ut focuses on the dark side of life (gambling, drugs, poverty and gangs)
Thanks everyone, I will check these out!!! I hadn't realized this thread was still going.
I +1 Golden Empire - contains some very strong romantic undertones, but nothing central to the plot. Temptation of Eve (mature content) Cruel City - the romance here is very understated, save for one episode. Time Between Dog & Wolf Le Jun Kai
Just seen I already posted here but I will recommend some more since I love dark shows. Not sure how dark are you talking so I will recommend different levels..

Very Dark
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Bump Off Lover - <<<<<<< Already recommended but its so good lol..
Lost Days - Subs still not completely finished being subbed but its dark and they finally started subbing again
Zeni Geba - hard to explain since I have not seen in a while but it was definitely dark.
Utsukushii Rinjin / Saki (sequel) - Girl is like a femme fatale kind of thing
Limit - Very dark but.. I feel it could have been better.
Unconditional Love - Short.. but very dark.
Sealed With A Kiss - Was very dark till around 60% then started changing thats when I put it on hold. It was so good before that though so maybe in the next episodes it would pick back up...

Dark
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Bad Guy - Guy wants revenge..
Ice World - Police officer falls for girl who is the most likely murder suspect
Edit: Didn't read the social issues part. Try Nobody Knows or Sayonara Itsuka (not really dark as in drugs, but more of a moodier tone).
Liar Game Karamazov no Kyodai Kazoku Game

Save Me was dark and creepy (dealing with a religious cult)

Watched most of these and adding the rest to my PTW list. This seems to be the genre I gravitate towards :-)

Autumn Tale (aka Autumn in my Heart) deals with issues surrounding acceptable relationships...2 siblings....family finds out one was switched at birth....the two fall in love, but family won't accept becuz raised as siblings even though unrelated by blood and the one sibling was returned to the other family.    All about social mores.