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Vampire Hunter D is the future of the Hellsing universe.
After Integra's death, Alucard "slipped his leash" and decided to conqueror the world under his real name, Dracula. He succeeds, establishes a kingdom of vampires, but becomes disgusted and annoyed by his childer's behavior. Que a massive purging by old Alucard which leads to downfall of the vampire ruled civilization, causing a new dark age. At some point, either before the purge or during it, Alucard has a tryst with a mortal woman and the result is D.
- According to the novels, humanity brought on its own ruin through a nuclear holocaust, and the vampires stepped in when they decided that they would be much more worthy rulers of the planet than the humans who nearly destroyed it, and the end of the vampire civilization was caused by the hubris of immortal creatures who had seen and done it all, and lost most of their vitality and drive; a slow decay that took thousands of years to culminate in the new rise of humanity. Though it doesn't necessarily mean that this WMG is without merit - just that it needs to be revised a bit on the details.
- Possible, considering D looks suspiciously like Alucard and wears basically a blue and black tieless version of Alucard's outfit.
- This might possibly be canon in the webcomic And Shine Heaven Now. Spoilers for the Grand Finale ahead: As it turns out, the boy that will become D was born between 1999 and 2014. He believes himself to be the child of Alucard and Integra Hellsing, something Integra doesn't dispute, because the more complicated truth is that he's actually Integra's son with Seras Victoria.
Alternatively, Vampire Hunter D is the Bad Future of the Castlevania timeline
The great big disaster which wipes out humanity happens in 1999 and D is said to be Dracula's son through "Mina the Fair". Sounds like Julius and company fell during the Castle War, with Alucard being either another casualty or suffering untold years of imprisonment and/or torture as a result. Doris Lang and Leila are related.
The two of them have the same eye and hair color and, though there are significant artistic differences between the two movies, appear to have the same sort of body type and facial features.
Since there's not a specific time as to when the stories are set in relation to each other, this could shake out two ways: Either Doris is the young girl that talks to D as he puts flowers on Leila's grave at the end of Bloodlust, or she is Leila's mother, who was turned by vampires and eventually murdered by the townspeople, inspiring Leila to become a hunter.
- Likely jossed by the books, which are set in a sequential order of events, though they do not say how long the time is between one story and the next. This would make it impossible for Doris to be Lila's granddaughter (though given her appearance in the movie, it was probably a continuity nod to Doris, whom is most closely associated with D in America prior to the release of the second film and then the release of the translated version of roughly half the book series.), though it is possible that Doris might be Leila's mother, however that raises the question of who the vampire was that changed Doris since we know that D killed off Magnus Lee and by proxy, Lee's daughter Lamica, who were the first book and film antagonists.
- Also likely jossed in the novels cause Doris has dark hair and eyes while Leila blonde and blue eyed.
- The Bloodlust movie is an adaptation of Demon Deathchase, which is the third book. In the fourth book, there's a young-ish doctor who is heavily implied to have met and fallen in love with Doris, before he ultimately moved on because she literally would never get over D. Which implies that Leila and Doris are not so wildly apart in age that they could be related. Plus, the novels also state that the Marcus clan all got experimented on by their parents, which is why they have powers. Doris seems like a woman with a good head on her shoulders, but I don't see her raising an experimental geneticist, especially not one who experiments on newborn children.
Dracula is really a Tragic Monster
And D will die along with him, after they both save the world and set it back on the path to restoring itself.- This is actually rather supported by the fact that the primary thing marking D as Dracula's only success is his ability to resist the craving for blood and cruelty that most Nobles and Dhampirs naturally possess and invariably succumb to. This could imply that Dracula's ultimate goal is to put an end to the violent state of human-vampire interactions. Though he is certainly more than willing to employ some extremely unsavory methods to reach said goal
The world D lives in is a possible future for the Monster Hunter world.
- He's clearly wielding a Long Sword, a type of weapon commonly seen in the MH universe that requires skill to properly use. His armor might be made from some sort of monster he tangled with in the past. As for why you don't see him chasing off creatures like the Alatreon, that's easy: the areas he's usually in either don't have many monster attacks or there are hunters keeping them in line.
Either Michael McConnohie or Andy Philpot will reprise the role of D in Vampire Hunter D: Resurrection
The elderly person who hires D at the start of Bloodlust is Dan Lang
- It has been a long time since the first movie, and it would make sense than Dan would call on the best vampire hunter he knows. This would make Doris as Charlotte's aunt, and no relation to Leila
