A show where MC reaches Steins Gate / Re:Zero despair levels

For those of you who watch anime - do you know any j-dramas/k-dramas that give off similar vibe to these two?

For those of you that don't or want me to elaborate what I yearn for specifically:
- MC keeps attempting to achieve a certain result/fix something he has done, but ends up getting worse and worse outcomes or solutions only working short term but quickly leading to new problems
- this takes a toll on his mental health & makes him to fall into despair/experience mental breakdowns/show signs of insanity
- mostly serious/dark atmosphere

These themes are often present in time travel shows (that I really like), but I'm open to anything that meets these criteria. Can be supernatural but doesn't have to.

Shows I've already seen that somewhat sufficiently satisfied that itch:
- Train
- Death's Game
- Signal

 The Long Night if you're ok with it being a c-drama. 

 Phobossus:

Thanks for suggestions! Yes I'm fine with c-dramas too, just like the Chinese language less.

The Long Night looks really promising, added to PTW. Is Burning Ice an actual prequel or just loosely related story?

My Lethal Man looks good too. Other 2 I think are primarily romance focused? (I usually avoid those)

W is a mix of romance and action (about the same as Train, I'd say), Present is Present is definitely romance focused, yes.

Probably:

• Kazoku Game
• Remember: War of The Son
• Reset (China)
• Revenant
• Someday or One Day (Taiwan)

I also remembered:
Boku Dake ga Inai Machi (Erased)

And this anime: Summer Time Render: https://anidb.net/anime/16033 (maybe you already saw)