I'm looking for a dark manga. Where the situations in the MC life make him fearless

And by dark I mean something like

Ningen shikkaku

I want in my face realities. Super plot and character that strikes home. let's take Yozo oba what goes on in the mind what has made him what he is. As far as world building goes I want something extremely realistic.

Read titles like
Shamo
Homunculus
Holyland
Owari no e tabi
Ultra heaven
holyland
Many more these are the ones that i recollect

Pls do not suggest clichéd mainstream ones
I'm strictly looking for gems.

Black Jack
Devilman
Wolfsmund

[img]http://www.dragonflycave.com/wpay/mew.gif[/img]

Ajin

[img]https://i.imgur.com/6MBFpsv.png[/img]
ᵂᵃʳᵘᶦ ᴷᵒᵗᵒ ˢʰᶦᵗᵃᶦ ᴳᵘᶦᵈᵉ | ᴳᵉⁿᵉʳᵃˡ ᶦⁿᶠᵒ | ᵂᵃʳᵘᶦⁿᵉˢˢ

Completed that

@Transdude1996
Thx for the recommendations will give them a shot black Jack looks cool after all tezuka osamu. But could you give me more options?

7 Seeds maybe
Bokurano maybe
Black Lagoon maybe
Eden - It's an Endless World!
Eternal Sabbath maybe
Historie
Jiraishin
Kurosagi - The Black Swindler
Shin Angyo Onshi maybe
Vinland Saga