I can honestly say that there are not many titles like it. It is truly something exceptional, roughly on the level of Gunbuster and Neon Genesis Evangelion. This is a dark, tense, grim, dramatic and very interesting story that keeps escalating, and escalating and escalating and in the end it has a very small number of flaws. The anime surpassed all my expectations, and I picked it by accident.
It is worth metnioning that it has very little in common with Devilman Lady manga by Go Nagai. I saw the manga, and due to standard nagai style and its age it was a bit hard to take it seriously. Rather than copying story from the manga, however, this anime reimagines it. Characters are similar to the original, but events are different. Jun is no longer a school teacher, but a photo model, and I bet events take a very different turn.
However, because it was a "reimagining" and not an adaptation, it suddenly turned into a masterpiece level material. From the amazing intro you get a good idea of what you're getting yourself into - a dark setting where everyone can die, nobody has a plot armor, and where even protagonist isn't safe.
Due to original material, there's a high level of violence, there's sexual tension, VERY strong yuri overtones, and people get into a really bad situations all the time. So it is not a lighthearted and happy show, but rather something that can keep you on the edge of your seat. I would say it is a horror show.
It is worth mentioning that anime managed to match all my interests, so I'm probably biased. Honestly, I was awed by it, but I'll try to provide a detailed breakdown below:
The story is grim. Starting with fantastic/supernatural premise, it keeps unfolding, evolving, escalating, and going further and further to a fairly unexpected conclusion. Rather than concentrating on individual characters it feels like it shows how the world slowly change around the protagonists. The story keeps pushing tension level higher and higher, and on many occasions you'll be watching the show and seeing that something horrible is about to happen. Rather than shying away and averting some sort of horrible event, the script lets it happen, and you get to see the results. The thing is... it doesnt' feel forced, unnatoral, and looks completely believable (unlike, say, Re: zero who went overboard with torture and that shattered illusion of the movie). Rather than going for the gore (as many titles do), the story focuses a lot on psychological tensions, so there are many tense, or uncomfortable moments, or situations that are scary when you think about them.
In the end it is "anyone can die" kind of experience. Limbs can start flying, but then rather than showering you with gore, the show starts playing with your mind, and demonstrates psychologically tense moments.
So all in all, it is very good. The only weakness is few issues with the main heroine (I'll talk about them later), and one "flashback" episode that appeared out of the blue and was quite weak compared to the rest of the movie. There also was one VERY predictable story turn I didn't really enjoy and felt like its quality was below the rest of the show.
It is okay. It is a quality 90s animation, on lower level than Shin Cutie Honey was, but nevertheless it is very detailed. Monsters are well drawn, but a lot of scenes happen in the dark (meaning you don't get to see muhch), and there were few (meaning one or two) occurrences where cels and scenes were reused near the end. I suppose the studio either briefly had budget problems, or were gathering resources for the finale.
It may be worth mentioning that there's less nudity compared to original (for example, devil lady is slightly censored), but still it happens plenty of time.
Music is magnificent, I loved it. Intro song has amazing gothic feeling to it, and music matches the show very well. The composer was pretty much a genius. IT is worth mentioning, that due to the gothic feeling about it, the soundtrack is fairly unusual. It is not a standard anime music by any means, regardless of the anime epoch. Then again I wish music like was used more often.
Characters have overarching motives that go throughought the show, and are fairly believable. However, in theory they could be portrayed better. Main heroine can be extremely annoying at ties, due to her impossibly meek nature. However, anime spends a lot of time concentrating on side characters (that tend to die quickly), and in those scenes it shines. I think it sorta reminded me of Hell Girl or maybe xxxholic in its structure - because quite a lot of episodes indirectly revolves aroudn someone else's story.
Absolutely amazing. I did not expect it to be this good and enjoyed majority of it. There were few issues where quality took a brief dip, but final events made it all worth it.
It is a must-see anime. The only reason why you'd want to avoid it, is if you don't like dark titles, terrifying/tense events, violence, sexually tense moments (can't pick a better word for this), or "anyone can die" scenarios. It is not a light hearted show. But it is a very good one.
Definitely check it out.