Disclaimer: this review covers the 1987 OVA "Devilman - The Birth" and the 1990 OVA "Devilman - Demon Bird Sirene," commonly packaged together as the "Devilman" OVA series."Devilman" is a well-known property in Japan, but less so in America. For a long time, despite the numerous manga, novel and anime adaptations, the only significant release was that of the "Devilman" OVA series, consisting of two 50-minute episodes. These OVA were probably not particularly well-known, but remembered fondly for imaginative and grotesque monster designs, and a bizarre English dub. The character would slowly grow in popularity outside of Japan, reaching its peak when "Devilman - Crybaby" was released internationally on Netflix in 2018. Thanks to this, the franchise became a significant part of anime culture around the world, with English fans finally being able to read much of the manga and watch different adaptations of the anime, some of which was only available on home video thanks to catelog-anime distributor Discotek. The original "Devilman" OVA series was released within months of the new Netflix series on DVD and Bluray. But how does it hold up? Firstly, keep in mind that the two OVA episodes are their own do not tell the whole story of Devilman. I haven't read the manga, but based on the compact "Devilman - Crybaby" series, the OVA reached about half-way through the main adventure, lacking one or two final episodes that would have provided something to a proper conclusion. There was a third OVA called "Amon - The Apocalypse of Devilman," released in 2000, a decade after the last OVA episode: while the same length and considered an unofficial continuation (even sporting a similar production style, despite improved quality in other series by this time), it was by a different studio and director, never properly received any English release as far as I can tell, and cuts short just before what would have been a definite ending. Author Go Nagai's stories are an acquired taste, but even if you already knew and loved the "Devilman" story, the OVA will leave you wanting. It is best intended as a supplement to see a portion of the story animated, and not much else.In "The Birth," we see the beginning of the story. First is an abstract series of images displaying what we presume is what the world looked like millions of years ago: demon after demon of disgusting design, fighting to kill and devour each other, even reveling in seeing the destruction of their enemy of the hour as they themselves are ripped apart. It is revealed that these are, literally, "demons," the same definition as we would know them. Monsters that sought only for destruction really once existed. In modern day, Akira is a boy who dislikes pain and death, courageously standing up to local bullies in his school. He is quickly visited by an old friend, Ryo, who whisks him off to explain his father's discovery of the existance of demons, who live even today, and claims the only way to fight back is to let a demon overtake them, but overpower the psyche of the demon and take control of its strength. Through an entirely experimental process, Akira is successful in serving as a host to the powerful demon Amon, and with the mind and heart of a human, becomes "Devilman!" Not just "Devilman"... but "DEVILMAAAAN!" In the second OVA, titled "Demon Bird Sirene," Akira continues to find and fight demons living in the underbelly of Japan, ultimately fighting a great female demon rival, a harpy-like creature named "Sirene." Seeing a teenager transform into a demon at will and loudly proclaim to his foes that "I'm not a demon... I'M DEVILMAAAAN" makes the property seem like a juvenille superhero fantasy. In fact, the original anime series of "Devilman" was a toned down child-friendly cartoon. But the longevitiy of the original manga, and in these OVA, is that it proudly an adult horror work. In anime, this wasn't a unusual genre in the 1980's and 90's, and you can easily find several direct-to-video films and episodes dedicated to extreme violence and gore, sex and nudity, released without any fear of censorship by television broadcast. Despite all that exists, I don't know that I've seen anything quite as grotesque as what appears in the "Devilman" OVA. Those first few minutes of the first episode was a great individual piece of primival violence for survival. Throughout, the demon designs are inventive, and the animation doesn't shy away from showing demons or humans being split in two. By the second episode, Akira's potential love-interest Miki, normally serious and level-minded, is displayed fantasizing about Akira embracing her as a woman, while taking a bath fully nude (all while a small army of demons invade the house and plan to attack through the very water she's in). 
If there is anything to appreciate in the OVA, this is it. For the audience of the time, it was a satisfying channel of sex and violence and demonic horror. Even the terrible English dub prodcued for the anime was made in this tradition. Not caring about subtlety or emotion, or sometimes even competent lip-syncing, the dub casually toses profane swearing in casual remarks, and nearly every line feels like it was awkwardly or jokingly delivered. It was an R-rated anime, after all, so why not double-down on foul langauge for the ratings board and further attract that audience? Often, this results in a couple good jokes, but often the series just comes off as absurd for the dialogue. So much so, that the OVA becomes far more watchable with the dub. Seriously, if you haven't heard classic lines like "how the hell have you been keeping, then?" or "Fucking-A, run for it," then you really must seek some online videos to listen to parts of the dub yourself. If you want to treat the OVA with any respect, better to try the Japanese dub, which is generally better, but even it will use a few clever one-liner jokes that the English dub doesn't. It was written from the start to be a fun experience, not a serious one.But aside from the violence and the (partially accidental) humor, the "Devilman" OVA doesn't have much going for it. Pacing can make the short series a chore to sit through, and as mentioned, the story is almost non-existent. Aside from the clever monster designs, the production values are weak even for a legacy Japanese anime, with most character designs not standing out or being particularly attractive, and only brief seconds of animation throughout coming across as a sign of skill by its artists. While the children's television series has a now-iconic theme song, the OVA has little to no music, and certainly little of it particularly good. When so much of an animated work is sub-par... what left is there to recommend it?Even if you are in the market for some violent anime from the punk era of the 80's, there are better choices. The "Devilman" OVA is only watchable by anime historians, those interested in all content from the franchise, or for people who take delight in watching a bad English dub in any foreign work. And when other options to experience the story exist, along with the mature content it is known for, then its value diminishes even further. That English dub is a treasure though. I'll keep a copy, if only for that wonderful mistake.