There are many factors that can make an anime truly disturbing: gruesome violence, emotional turmoil and instability, nudity, the horrific events a protagonist must endure, the subject matter, etc...
I would like to know which anime has truly disturbed you through its viewing; which anime had you horrified yet intrigued as to what came next, left you wondering how they could the portray something so awful, and finally when it ends you wish simply for more.
The anime that has instilled these feelings in me is Elfen Lied.





Again, I have to go back to Eiken & School days, they may not be bloody (well at least SD isn't till the very end) But both are very painful experiences to sit through, they make my brain cells cry out in pain!
Oh also It can be pretty hard to sit through Juden-Chan, which is another show thats just plain bad.
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Speed Grapher, couldn't stand the show for how...well, for everything it had in it.
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Tokko or Elfen Lied, the disturbyness was fun.
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From what I've seen, it'd tied between Elfen Lied and Deadman Wonderland.
School Days isn't disturbing, it's just awesome.
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Elfen Lied and sometimes DeadMan Wonderland. It would shine ever once in awhile
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I have to say is the Futuer Diary because the stroy will make you cry in the end it will shock you.
Queen's Blade. I bailed out of it before I even made it thorugh the first quarter of the first episode.
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We need to dig a little deeper back here if ya ask me ^^ Not much can top some of the stuff from the 80' and 90's in terms of disturbing visuals and extremely graphic violence at least. Take the Devilman OAV's for instance, pure blood and gore. I love me some intense violence in my anime, but even I had to sit back and go "Holy..." for some of those scenes. Then there's the Genocyber OAV's, the first and second episodes easily fit the bill in the disturbing visuals department if I remember correctly, it has been a while though.
Don't get me wrong either, these may be disturbing to watch and all, but this is disturbing in a good sense to me
Oh, almost forgot, M.D. Geist. Objectionable content out the wazu and extremely disturbing, but not in a good way. Wish I'd never watched it...
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The anime that has instilled these feelings in me is Elfen Lied.
The way you explain it, this anime is the embodiment of disturbing - which is very different from bad - I agree with you 100% on this. Elfen Lied is a disturbing anime and I think that is the intent of the story to do so - I found it disturbing as well, but good, yes.
I was waiting for someone to mention this, I love the show, but the first few minutes of the first episode really do push some limits, so I can understand if it scared some viewers away - I think the only other anime that surpasses it in this department is Seikon no Qwasar - to me, it seemed like it was their intention to show up Queen's Blade.
Awwww, I loved this anime, but, so you didn't like it, no big deal.
For me, there are three categories to slate disturbing anime:
1. Just bad, and disturbing anime that makes funny situations of things that are creepy - Green Green, that one guy that wants the small girl, he was so errie - "I want her to be my litte sister!" he says - "what a vulgar character." I say. Then there's Eiken - I'm sorry, a 6th grader with a massive rack, sick - this prooves that you don't have to have "real" nudity to make obscene fanservice that rivals Queen's Blade and even Seikon no Qwasar - and the fanservice was more disturbing and gross on Eiken, no wonder it went for only 2 episodes.
2. Disturbing, but good anime - Elfen Lied, as I said, it was supposed to be distrubing, it covers so many dark themes, as a viewer, if you're not feeling uneasy watching you're either desensitized, don't care, or weird.
3. Animes with disturbing parts - I thought both FMA alchemist series had a few that left me uneasy:
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