There are subjectives, and then there are these. While you may believe a work fits here, and you might be right, people tend to have rather vocal, differing opinions about this subject. Please keep these off of the work's page.
Ignore for a few moments the great Subbing versus Dubbing debate among the anime fandom. There are certain shows or works in that medium that fail on their own merits and prove that being So Bad, It's Horrible is not exclusive to any one side of the Pacific. You know it's bad when even fans looking for a Widget Series exclaim "WTF?!?!?" after viewing. Feel free to curse these titles, anime haters — the fans don't bother defending them, anyway.
Important Note: Merely being offensive in its subject matter is not enough to justify a work as So Bad It's Horrible. Hard as it is to imagine at times, there is a market for all types of deviancy (no matter how small a niche it is). It has to fail to appeal even to that niche to qualify as this.
Second Important Note: An anime isn't horrible just because Bennett The Sage, Professor Otaku, Don East, The Other Side, Doggy D. Dachshund and Conroy Cat or any other Caustic Critic reviewed it. There needs to be independent evidence, such as actual, professional pannings, to list it. (Though once it is listed, they can provide the detailed review(s).)
Examples (more-or-less in alphabetical order):
Ail Maniax, a series of three episode 2001 hentai OAVs from Pink Pineapple, takes porn without plot to such an extreme, and then crosses it over with torture porn. The plot can loosely be explained as a demon violently molesting women throughout centuries from a Catholic nun in the Dark Ages in Europe to a Shinto priestess in modern era Japan. The "story" is told anachronistically, and a great amount of the run time each episode is dedicated not to weaving a story, but showing an utterly depraved violent rape that lingers on and on. At the end of series, in Episode 3, the demon violently rapes the Shinto priestess who set out to seal the demon away at the beginning of the series, and is discarded in the middle of park, presumably dead, if not traumatized, and that's the ending. The bad guy wins, with no point to be made. There are zero likable characters, the animation and artwork are underwhelming, and it's directed by the infamous Teruaki Murakami and a majority of the hentai he directs are every bit as bad as this.
The anime adaptation of Amnesia (Otome) is often used as a shining example of why anime of otome games are usually awful. It has a convoluted plot that tries to be intriguing but instead comes across as confusing and pretentious, ugly and garish character designs, characters that are either extremely bland or unlikable (including a nameless Too Dumb to LiveFlat Character as the main protagonist), quite possibly the most poorly handledyandere in anime history, and oodles of misogyny (despite being aimed at a female audience). When Sentai Filmworks announced both a English dub and a Blu-ray release, there was actual outrage from anime fan communities as to why it was deserving of it (it was allegedly to promote a possible english release of the original visual novel, but still).
Art of Fighting had an absolute mess of a 45-minute OVA, with a ridiculous story, depressingly predictable plot twists, and not one interesting or likable character. Heck, the one thing you'd expect it to be able to deliver (spectacular fights) falls flat. And from a video game player's point of view, it has nothing to do with the story of the games beyond the premise of "Yuri gets kidnapped, Ryo and Robert try to save her", none of the signature special moves appear and Ryo has black hair for some reason. About its only saving graces were the decent music and turning Butt Monkey Ryuhaku Todoh into a hilarious nutcase police chief. Watch Bennett the Sage tear it apart here.
Fun fact: The voice for Yuri Sakazaki in this clunker is J-pop singer Ayumi Hamasaki, who made her first (and only) voice acting role.
The Cosmopolitan Prayers, a.k.a. Cosprayers (not "Cosplayers", Cosprayers). The broken English in the title is the least of its problems. The characters are incredibly idiotic, inconsistent, and one-dimensional. The girl who loves the male lead makes out with the main (female) protagonist, and the other girl also likes the guy, and there is no motivation for the Triang Relations. There is random unnecessary Fanservice alongside loads of rape imagery which makes anything potentially titillating just plain creepy. There are no transitions — one minute, everyone's chained up in a cave; the next, they're on a pier fighting with tennis rackets (a power upgrade, by the way). It has a plot that must have been thrown together between rounds and the conflict and characters never give the audience any reason to care. It heavily rips off Power Rangers, only it's much less entertaining. It culminates in an extremely lazy Gainax Ending with singing and rainbows... no, seriously. The whole thing was made by the company M.O.E. (Masters of Entertainment), but they don't show their mastery here.
To add insult to injury, there's two spinoff shows which portray this as bad in the Recursive Canon, to the point where in the second series, it turns out the identity of Cosprayers's writer is kept secret from the public eye.
Dark Cat, an obscure horror OVA from 1991, suffers from many problems such as an unfocused narration, lifeless, uninteresting characters and ugly, practically artless animation. Not to mention the horrific English dub. One of the many direct-to-video OVAs that flooded the market in the late 80s/early 90s, it is best to be left forgotten.
The anime adaption of Demon Beast Invasion suffers from terrible animation, extremely lousy art, poor characterization, and an awful and misogynistic story about an alien demon (who constantly shouts 'MOTHER' to the point where it becomes irritating) that wants to rape women and take over the world.
The Diabolik Lovers anime tries to be a Guilty Pleasure, but manages to fail even at that. It contains bland animation, extremely unlikable characters (the male leads are all creepy assholes and the female lead is supposed to be The Woobie but is as flat as cardboard personality-wise), loads of squick, very misogynistic elements, insensitive and disgusting attempts to fetishize realistic abuse and Stockholm Syndrome, and a stupid and contrived plot. Each episode's only about 15 minutes, but they feel like hours.
And apparently it's getting an English dub courtesy of Sentai. Like with Amnesia above, there was a lot of rage.
The Yaoi Genre manga Dog Catalogue, with its ridiculous use of 2D characters, a frightfully generic storyline with absolutely no development in the characters and with arguably some of the worst art put to paper◊. Every page is an artist's nightmare.
The Eien no Aselia: Spirit of Eternity Sword OVA adaptation. The game's great; the OVA... not so much. The plot is nothing like that of the game. The pacing is horrible, the animation below average, and the background music is copypasted from the game. The characters have almost no resemblance to their video game counterparts. It's as if the staff made this anime on a lunch break. Thankfully, it's only two episodes long.
Genma Wars, a spinoff of Harmageddon, of all things. There are two major reasons why this series from 2002 failed so very, very hard:
The Gratuitous Rape. Now, to be fair, the series is predicated on one sexual assault: A young woman offers herself up to the Evil King to save her clan from raiders, and conceives half-breed twins. But then, one of the twins is taken to eke out a miserable existence among the Evil King's subjects. After he grows up and leaves the King's castle, he meets a woman and, after being at least somewhat friendly and decent to her, decides to assault her, too. Without so much as a "get away you bastard", she doesn't fight him off. She doesn't even seem to understand the way that she was violated, and pontificates to the effect of, "It felt like his life force was entering me..."
The horrible, horrible animation. It is often recycled, cheap, awful, and so very digital. For example: the "good" Wild Child twin has a wolf for a guide after his mother perishes, and he can talk! The problem? The wolf's jaw literally just flaps up and down. In a better series, it may have been justified, but in this series, it just adds to the seeming laziness of the production crew. His jaw literally hangs open for a few seconds at a time as he "talks", and his English VA has a hokey, Speech-Impaired Animal voice to boot.
Honey X Honey Drops, a two-part OVA adaptation of the shoujo manga of the same name. Unlikable and flat characters, underwhelming art and animation, and a very degrading and misogynistic plot that's basically about a teenage girl forced into prostituting herself. Nearly every review on My Anime List is a warning to avoid it.
The anime adaptation of I Don't Like You At All, Big Brother!! has unlikable and poorly-developed characters, a dumb plot, tasteless fanservice that's often very gross, lazy writing that mistakes Lampshade Hanging and sex imagery for humor, and a very ugly and off-putting art style that clearly wasn't meant for animation, let alone an "ecchi" series. Even fans of the imouto genre (known for its often low quality series) hate it.
Ijime, a short anime OVA released free in a issue of Ciao (which should tell you a lot). It has amateurish voice acting, flat animation, a hideous art style so far in the Uncanny Valley it hurts, and clumsy and melodramatic handling of serious subject matter (childhood bullying). There's also a scene that plays out like a gang rape. You have been warned. It's very telling that it's the only Ciao Ciao TV short so far that never became a mini-series.
The anime adaptation of Koi Koi 7 does everything one should not do when adapting from a manga. The animation quality is shockingly bad and the design of the mechs and the characters is blatantly ripped-off from far superior shows (the mechs from Gundam, for example). As if the technical shortcomings aren't bad enough, the plot is compressed to the point of being totally bland and leaving virtually no sign of character development nor meaningful action whatsoever. Above all, it's crystal clear that the seiyuus and the music composer phoned in their performances, as the voice-acting and the soundtrack are bland and utterly terrible to listen to.
The Kyo Koi O Hajimemasu OVA was made by the same people who did Honey X Honey Drops, and suffers from pretty much the same problems, including flat animation and voice acting, unlikable and/or bland characters, a cliché and uninteresting plot, misogyny, and zero attempt to make sense to viewers who haven't read the manga.
The anime adaptation of Mamotte! Lollipop, made by a no-name studio as a cheap cash-in on a mildly popular series. The manga itself is So Bad, It's Good, but this is just bad. Bland and/or unlikable characters with designs that are either generic or garish, cheap animation (even for 2006) that's constantly reused, a very poor grasp of its target audience, an atrocious English dub that mostly consists of screaming and yelling, an uninteresting romance subplot, and a downright stupidCliché Storm plot with a Gecko Ending even though the manga was already finished long before it came out. Anime News Network states the only people who could possibly like it are little girls who don't know any better. It's one of the very few anime Funimation seems to treat as an Old Shame (in fact given their handling of it they likely knew it was terrible when they got it).
The short promotional OVA Marimo no Hana has awful voice acting (a preteen boy has the voice of a screechy little girl, among other examples), terrible pacing, stupid characterization, and a vague, borderline nonsensical plot filled with Mood Whiplash. Its only saving grace is that it's actually decently animated, but sadly not enough to make it worth watching.
There's an another Idea Factory anime with the same director, Tenkuu Danzato Skelter Heaven, which is a very similar failure to Mars of Destruction, except the visuals are much better. It's no wonder why Idea Factory stopped producing anime and instead focused on video games, and Yoshiteru Satou didn't get the rights for directing the Hyperdimension Neptunia anime.
Most anime by Yoshiteru Satou seems to be this. One comment on My Anime List called him as the Ed Wood of anime, and his best anime only got 6/10.
Ninja Resurrection, based on the novel Makai Tensho by Futaro Yamada, and falsely marketed in the US and UK as a sequel to Ninja Scroll, has horrible no-name voice acting that makes the words "Tokugawa Shogunate" a Brown Note, extremely gross and misogynistic fanservice, and a nonsensical plot about Amakusa with a Devil in Plain SightEvil Chancellor leading to the pointlessly squicky resurrection of Amakusa into Satan where his new evil cronies begin slaughtering townspeople... and on top of all that, the series finally ends there due to people wisely avoiding any further trick-marketing.
Some could argue that the series ended just as it was about to get good (it actually ends as the antagonist groups leap off-screen, implying a big showdown and/or massacre to come). It also features Mataemon Araki, the only likable character by virtue of being a gigantic badass who kills ninjas with combat tentacle entrails. He has barely three lines, but is somehow one of the most fleshed-out and interesting characters.
Pure Love, aka Rhythm, is a HORRIBLE excuse for a hentai that has dreadful animation and artwork that literally looks like it was done on Photoshop, a non-existent story, ugly sex scenes, awful characterization, and a terrible English dub. Luckily, it's only two episodes long.
Pilot Candidate / Candidate For Goddess had Horribly-integratedCGI even for its era, plot holes practically from the start ("Only men can be Goddess pilots... except for this lady"), and an aggressively unlikable protagonist in Zero Enna (imagine an easily-excitable combination of Ash Ketchum, Amuro Ray and Taichi Kamiyanote Joshua Seth (working under a pseudonym for PC) provided the English dub voices of both Zero from Pilot Candidate and Tai from Digimon, but with none of the redeeming qualities of any of them). The greatest failing, however, is that every piece of the story is incomplete. Several characters and concepts are introduced but never explored, each battle is an unfollowable mess with key points missing, and while the focus on cadets should make for an interesting angle, the main characters are barely involved with the plot. And to top it all off, even though the story is too thin and weak to support twelve episodes, it still has a Gecko Ending.
Interestingly, the series was based on a longer manga by the author of D.N.Angel, but the company who animated the series declared itself bankrupt after releasing the last episode as an OVA. It also made the author very hesitant to allow D.N.Angel to get an anime adaptation. Eventually, XEBEC (producer of this series and of Martian Successor Nadesico) made a competent adaptation.
[adult swim] aired this anime once, when the block was still finding its legs. And we do mean once — this is one of very few shows that [as] never showed again after its initial airing. A commercial bumper over five years later said, to paraphrase, "Pilot Candidate: Never Again."
What's worse is that it was originally going to be on Toonami (back when Toonami was a daytime action cartoon line-up) and was edited down to Toonami standards, making it more incoherent. When Adult Swim decided to air it, it was the Toonami-edited version.
Locomotion, a (now defunct) Latin-American animation channel, dubbed the whole series to Spanish, and in the period before changing hands they repeated this daily since it was one of their few anime left. Not even the (surprisingly good) dub could save this series.
Psychic Wars, a 1990s OVA that suffers from a nonsensical plot, boring characters, flying plot leaps, and bad pacing. It was originally going to be a three episode miniseries, and unsurprisingly, only one episode was made due to its low budget.
The anime adaptation of Pupa. For one thing, fans of the horror genre had high hopes for it due to the lack of good-quality horror anime, but then it was postponed from its original Fall 2013 line-up, and pushed back to the Winter 2014 line-up, where it was revealed the episodes would only be four minutes long (which is its only saving grace, according to viewers). It's been universally panned for horrid writing and piss-poor pacing (including a sub-plot that was the dropped the moment it was introduced), uninteresting characters, mishandling of the manga's disturbing material, shoddy censorship as it was airing, simultaneously disgusting and dull "scares", and a final episodethat did nothing to wrap up the plot. Special mention goes to the infamous episode six (and eight when it comes to the censorship). Not only is it currently the lowest-ranked TV anime on MAL, it also broke Anime News Network's rating scale in its Shelf Life review, earning the column's first ever "Flushable" score. Anime Viking also has a few words to say regarding the matter. Oh, and the studio who produced it? Studio DEEN (nearly considered this trope when it comes to studios).
Root Search, a 1980s OVA with stiff animation; unlikable, poorly-developed characters; and a pretentious and incoherent plot ripped off from Alien. Here's a review.
Fans of the first person shooter video game Sin absolutely loathe its horrendous anime adaption Sin: The Movie and they like to pretend it doesn't exist for several good reasons. It's bad enough that the title of it is misleading on the box art (It's called 'Sin: The Movie' even though it's actually a 2 episode miniseries), but to make matters worse, major unnecessary changes have been thrown in. Examples include John blade being changed to a cyborg (even though he wasn't one in the original game), JC Armack is now killed off, and it is now set in the 2070s (even though in the original video game it is set in 2037). Other problems include mediocre animation and art, lame new characters that never appeared in the original game have now been thrown in, a few giant plot holes, and a bland story. it's painfully obvious that Sin: The Movie was created just to cash in off the success of the original video game it was based on.
The anime adaptation of Togainu no Chi has been panned by fans of the original game for good reason. Admittedly, given the nature of the game and its multi-route system, some elements had to be removed for the censors, but it still doesn't excuse the fact that so many things were removed from the story, people being introduced to the series for the first time didn't know what the hell was going on. Terrible animation (to the point that Episode 12 nearly completely consisted of animation recycling), constant deviation from character styling, and a mediocre script combined to make a fairly celebrated BL game into an animated train wreck. There are even rumors that the anime's staff deliberately sabotaged it (the reason why is currently unknown).
While it isn't surprising that certain parts of Tsukihime were changed for its animated adaptation, given the original visual novel's content and structure, what was changed is completely awful. The writing is littered with plot holes, outright bringing up important details from the VN and then ignoring the actual cause or context, the animation is cheap enough that a character falling is shown as a moving still frame, the music is dull and repetitive (the only good song is the opening, an awesome instrumental that makes the rest of the soundtrack even more boring in comparison) and, despite only being 12 episodes long, the plot often slows down to a dull crawl. Predictably, it was savaged by critics, did terribly and to this day Type-Moon fans pretend it never happened.
Urotsukidoji III: Return of the Overfiend shows exactly what can go wrong when making a sequel. The animation is dreadful, the artwork is awful, the soundtrack is abysmal, the new characters are appalling [for example one of the new characters is called 'Buju' and he rapes women, murders people, and shows zero remorse for his actions, yet for some strange reason he's the new protagonist], disgusting and misogynistic scenes of rape that come across as big lipped alligator moments due to adding nothing whatsoever to the story, and the story is very badly written and filled with pretty big plot holes. Many Urotsukidoji fans have ignored its existence altogether. and Urotsukidoji IV: Inferno Road pretty much suffers from the same issues.
Urotsukidoji: New Saga, a.k.a. The Urotsuki. A dreadful 2002 reboot of the original Cult Classic 1989 hentai OVA Urotsukidoji: Legend of the Overfiend. it has been criticized by many Urotsukidoji fans for having horrible animation (to the point where in episode 3, the animation almost looks like it was done on Photoshop), ugly and poorly detailed art, lousy new characters, terrible CGI that is often overused, unexplained plot points, occasional out of sync voice acting, and two very sick and misogynistic gorn scenes. The only saving grace to this train-wreck of a hentai is the pretty impressive soundtrack composed by Masamichi Amano. But apart from that, Urotsukidoji: New Saga should be avoided at all costs.