There are two kinds of people in this world: People who look at Batman and say, "Yes, Batman, hooray, forever, erection, Batman, badass, terrific!" and people who look at Batman and say, "Yeah, I see what people like about Batman, but wouldn't he be better if I ruined him?"
This article is about that second group.
Apparently vampires have no interest in basic cape maintenance.
Not a lot of time was spent on an origin story here. In this universe, Bruce Wayne starts off as the regular, human Batman that we know and fear. He wakes up one morning to find a woman biting him on the neck, and she's a vampire, and for unexplained reasons Bruce is totally cool with this and trusts her implicitly, because we all know Batman loves strangers who sneak into his home and steal his humanity.
"I'm cool as long as you didn't get red on the sheets."
It turns out Tanya's a vampire who has come to Gotham to ask for Batman's help fighting Dracula, and somehow, by turning him slowly over the course of a month, she has given Bruce all the strength of a vampire and almost none of the weaknesses or blood lust. This doesn't make any sense according to any vampire lore we've ever read, but any sense this book was planning on making gets thrown out the window when Bruce suddenly grows wings.
"Ain't nobody's going with God now, Alfred. It's pure metal all the way."
After blowing up Wayne Manor and Tanya herself in order to kill a few dozen vampires, Batman then takes on Dracula in an aerial fight for vampire bat supremacy, where he totally kicks Drac's ass in the fashion competition.
At some point in between fights Batman stopped off to buy 80,000 more yards of cape fabric.
Batman manages to kill Dracula, which one would think should just wrap up the whole Batman-as-vampire saga, but it goes on for a while. Batman continues to grow as a vampire and even develops the blood lust that he was never supposed to have to begin with. The blood lust is so strong, in fact, that he finally has to kill someone to survive.
"All his makeup has rubbed off on my face! I look like a giiiiiirrrrrl!"
"NO," he screams, "though this was great, I'm absolutely going to keep eating bad guys," he obviously thinks. Now that he's crossed over into full-on murderous vampire, he decides to go all Dexter on the whole city and proceeds to hunt down and viciously slaughter every single villain available.
Oh no. Somebody stop him. He's killing all the psychopaths in a really awesome way.
There's nothing like a monocle to class up your rampage.
To save himself some trouble in the future, Batman even kills the prisoners safely locked up in Arkham, because really, we all know they're getting out at some point in the next 60 days anyway.
"Warden? I think Batman's a ghost vampire made of blood, do you -- oh, that's the sense you're getting, too. OK."
Obviously something needed to be done, so Alfred and Commissioner Gordon agree to team up with Two-Face and Killer Croc to become a vampire-Batman-hunting team. ("Founding Member of Vampire-Batman-Hunting Team," by the way, is the single most impressive title anyone can ever put on a resume.)
Next of course would be "mutant croc" or "half a red skull rip-off."
This whole thing goes about as well one would expect, and it ends with Batman killing not just Two-Face and Killer Croc, but also Alfred, who offers his blood to redeem himself for betraying Bruce. Batman is tormented with as much guilt as a vampire can be expected to ever feel and asks Gordon to kill him now that Gotham is literally devoid of all evil except for him. Basically agreeing with him, Gordon blows up the Batcave, letting in the sunlight and killing Vampire Batman permanently, along with everyone else in the story.
But at least Commissioner Gordon will live to remember this tragic ... oh no wait, he gets crushed by a giant rock while trying to escape. Never mind.
At last, the city is ... oh shit, everyone's dead.
Round the corner from Batville, and twinned with Batingrad.
In Castle of the Bat, set in the 1800s, Bruce Wayne has of course had his parents murdered in front of him as a child, but is now a scientist instead of a Batman. While exploring the organ cellar of his university (sure!), he stumbles upon his father's brain.
"I won't ask why you had it, and you won't stop me from taking it. That's our deal."
See, in this universe, instead of trying to fight crime to avenge his murdered parents, Bruce has devoted his life to reanimation in an attempt to just bring them back to life. With the help of his hunchbacked servant, Alfredo, he turned to grave-robbing for parts for his Dad's new rocking bod.
Yup, that's Alfred Igor. Or Al Gore.
After digging up a sufficient number of giants to finish his mix-and-match Dad puzzle, Bruce shoots the corpse up with lightning (he is a very bad scientist).
"Of course he lives, why wouldn't a bunch of rotting meat struck by lightning not work?"
Unfortunately for Bruce, his creation not only lacks sentience and speech but is also the wussiest monster of all time. It immediately hides in the corner, as it is both scared of the dark and hurt by the light. So basically all aspects of existing suck for this poor thing he stuck his Dad's brain into.
"It's like nothing I do is good enough for you, zombie-dad!"
A few days later, Bruce realizes his father's brain is probably traumatized from all that dying it went through 15 years earlier, so he injects him with bat DNA to try to fix him. How is this supposed to help, exactly? Well, it means they can put the words "Batman" on the cover of the comic book, so that's really all that matters. The less believable explanation is that he assumes the monster will be less afraid of the dark if it becomes a creature of the night. Bruce also dresses his dad up in a cape, cowl and outfit with bat symbols all over it because ... well, that first thing we said about the cover.
"I just want my Dad's corpse to feel normal, so I'm dressing him up in a costume, OK, Alfred? Jeez!"
The bat DNA ends up making his father super strong and slightly sentient cause, yeah, sure, bat DNA is magic. Even though he can't speak or communicate, this new Bat-man is able to break out of the castle, track down and kill the highwayman who murdered him 15 years earlier, solve crimes, fight bad guys and rescue damsels in distress, just like a good Batman. Oh, and he did it all while looking like a surprised cat-head stuck on a huge man's body.
"HELLO I WONDER IF YOU'VE HEARD THE WORD OF GOD."
Eventually, due to some kind of bat-science related accident, Wayne's castle collapses, and when Bat-man rushes in to save Bruce, he gets killed in the process. Before he dies, we get to see a truly touching moment where the monster manages to speak his one and only word to Bruce:
"Oh yeah right, I remember this. I got so caught up in the whole bat thing, I forgot I had a Dad."