It's not anime, but it's deliberately trying to look like anime, it's based on a Japanese game franchise and I watched the Japanese dub. That's close enough.
That said, though, you can tell it was written in English and translated into Japanese, not the other way around. Here's how our hero (Trevor Belmont) describes a particularly unpleasant priest: "over the top and into new lands of just snake-fuckingly crazy." The Japanese dialogue isn't even trying to get there (and is, to be honest, far more bland). Swearing just doesn't really translate between those two languages, alas.
It's written by Warren Ellis, by the way. That might explain the goat-fucking conversation in ep.1.
Castlevania is a Konami computer game from 1986, in which you play a Dracula-hunting hero called Belmont. That one was a side-scrolling video game and there were a couple of scenes here that I was imagining as a homage to that kind of game. (Belmont + monsters + catacombs.) The franchise went big and it's still going today, but this mini-series is based on Castlevania III: Dracula's Curse (1989).
It's the 15th century and Wallachia is ruled by Vlad the Impaler. There are two stories here: Dracula (ep.1) and Trevor Belmont (eps.2-4).
EP.1 (DRACULA'S STORY): It's pretty good. Dracula's actually quite sympathetic, even after he's gone apeshit and unleashed the apocalypse. He's a perfectly decent chap if you're polite to him. He has a castle, a scientific mind and excellent manners. Unfortunately there's also the small matter of the Church, who come off as being a good deal worse than Dracula. Admittedly fairly soon he'll be trying to kill every man, woman and child in Wallachia, which is more achievable than it sounds since this is Dracula we're talking about. He can summon baby-eating hellspawn. They'll get the job done. Besides, he does at least give everyone fair warning and a whole year to get to safety.
The church, on the other hand, are the people who made Dracula angry. They're... let's see, what's the word? Oh yes. Scum. Their antics here include burning innocents at the stake for the crime of trying to educate peasants ("the archbishop prefers that life be kept simple"), telling people that their babies are being eaten because they're not religious enough and then believing their own propaganda (even though it was actually their own fault), branding the Speakers as heretics (which is a death sentence) and the source of all evil because they're not directly subordinate to the Church's authority, etc. Ellis isn't equating the Church with religion itself, though. There's a deeply satisfying exchange on this topioc in ep.4 between the Bishop and, um, something. You could have fun wondering how Our Blue-Fanged Chum knows God's opinions (maybe it's just expressing its own opinions and/or having a laugh?), but that doesn't matter because it's great to see the Bishop getting the situation explained to him so clearly.
Let me put it this way. This medieval Church is nearly as stomach-turning as the one in Berserk. However I see I've already got started on:
EPS.2-4 (TREVOR'S STORY): ...Trevor? Really? That's an amusing name choice, although in fairness Ellis had no choice there since that's what the protagonist was called in Castlevania III. (As it happens, the name "Trevor" was in use in that time period, but in Wales and Ireland.) Anyway, Trevor is the last of the famous vampire-fighting House of Belmont. Since this family was the only people capable of fighting back against Dracula's undead hordes, naturally the Church saw them as dangerous rivals and had them killed. Trevor (heh, Trevor) was the only survivor and unsurprisingly he's embittered (albeit in a self-deprecating, good-humoured way). He can be talked into being heroic, but you can't stop him from grumbling and trying to persuade himself that he should be walking out on these losers.
This mini-series is lots of bloody fun. It's only four episodes long and it basically ends on "To Be Continued", but Netflix have already commissioned an eight-episode Season 2. It's got spectacular gore, ultra-violence and a gleeful joy in vulgarity. There is much vomiting. Groins get kicked. Trevor climbs up a toilet pipe. Corpses get chucked on to a huge pile, eyeballs are left dangling from the scenery and you'll see heads on spikes. The second archer's death in ep.3 is particularly amusing, although you might miss it if you're not watching carefully. However it's not just mindless gore and instead has a solid emotional underpinning, with strong motivations and baddies who very much deserve what's coming to them. It's good for a laugh.