twisted and dark mangas

http://www.mangago.zone/read-manga/bastard_hwang_youngchan/

http://www.mangago.zone/read-manga/kokoro_o_korosu_houhou/

http://www.mangago.zone/read-manga/hikizuru_oto/

http://www.mangago.zone/read-manga/color_recipe/

Here's some

The creator of Bastard also has an amazing, twisted work called Sweet Home.

but u should read it on webtoon for faster updates

Not really twisted, dark or anything, but close

Gantz
Sekai oni
Jackals
Homunculus is also... pretty dark for me but not as twisted as what you want I think?

And my number 1 suggestion as of the moment?


Dead tube

Go read it (⌒▽⌒)

http://www.mangago.zone/home/mangalist/290539/

How dark are you willing to go?

Nishin Masumi has some really dark stuff (rape, gore, crazy ass characters). Feeding Lamb is darker, but I think this one and Host is Down have more interesting plots:
http://www.mangago.zone/read-manga/heartless/

If you're looking for twisted relationships (and ok with incest):
http://www.mangago.zone/read-manga/kusatta_rasen/

I cant find that manga where a man was used to bred pigs...

I don't think I've read that one.

Well, since you've started this dark road, I suggest you go back and don't read it. ╮(￣▽￣)╭

I'm not sure, I read it on MRM because you know, MRM has EVERYTHING. (≧∀≦)