I've already read:
Ibitsu
All Corpse Party
Tokyo Red Hood
Dolls Fall
Shiki
Chimamire Sukeban Chainsaw
All Tokyo Ghoul
Dark Metro
All Itou Junji
Screaming Lessons
Manga Of The Dead
School Days
Mirai Nikki
Elfen Lied
When They Cry
And a lot more.... I just don't want to write them all out.

I am not interested in High School Of The Dead.

I don't have a weak stomach or anything like that, as you can see (Tokyo Red Hood) lol

I love messed up manga.

Ichi the Killer
Basilisk

Thank You very much.. 🙂 If you have more.. let it come.. 😉 😛

Hiai Mousou horror/messed up
Saiteihen no Otoko horror/gore/messed up
Battle Royale messed up/gore
Gantz gore/horror
Doubt (TONOGAI Yoshiki) messed up/horror
Franken Fran the whole manga seems to be really messed up
Kami-sama no Iutoori and the sequel horror
Apocalypse no Toride horror/gore
Bio-meat: Nectar horror/gore
Homunculus messed up
Tsumi to Batsu - A Falsified Romance messed up
Drifting Classroom horror/messed up
Battle Royale messed up/gore
Doctor Du Ming horror/messed up
Goth messed up/gore
Melo Holic messed up/horror
Monster Not really messed up unless you don't regard a sociopath as normal
Wolf & Mary This one is short but I rather liked it. It's messed up and gory in a funny way

I personally have the same taste as you, I would say.

Chinese Translator Accepting translation requests if the manga interests me!

Thanks a ton. 😉