Vampires. Bloodsuckers, creatures of the night. Or, as they prefer to be called, the Kindred. These undead creatures need the fresh blood of humans to survive, cannot walk in the sun, and possess supernatural strength and stamina. They can be found in all positions and walks of life, from fancy CEO-types sipping their blood from crystal glass to horrors in the undercity who grab what they can get and run.
They look human, on a cursory glance. And many of them are good at playing the humans they once were. A chance encounter on a nighttime street ends in seduction as often as violence (and many vampires prefer the former - cooperative prey take less energy, after all). But their skin is still cold and dead afterwards, and they still feel the clawing, hungry Beast inside them, regardless of how many polite trappings they put on their society.
And it is full of polite trappings, intended to moderate and keep the Kindred from violence and full-ut war against each other. After all, many of them will 'live' for hundreds of years, growing in power and influence. Vampires society is organized into Clans (the kind of vampire you are) and Covenants (how you fit into vampire society... or don't). A small group of vampires is called a coterie.
All vampires hide from humanity beneath the Masquerade, a set of rules that keep them from getting too close to mortal affairs and being discovered for what they are. One person breaking the Masquerade is regarded as a danger to all Kindred - and taken down as such. The life a vampire leads among others of their own kind, away from the eyes of mortals and the fetters of the Masquerade, is called the Requiem.
There are as many myths and misinformations about vampires as there are people; outside of the Kindred themselves, everyone seems to give you a different story. One of the biggest involves vampire bites being immediately contagious; turning someone into a new vampire is actually quite a lot of work for the 'sire,' as what they call the Embrace requires a complete exsanguiation of the would-be vampire. The process is neither pretty nor casual, as vampire society expects the sire to be at least somewhat responsible for their new childe - of course, that's not always what happens.
If you want more detail in building a vampire character, this site is a good reference, or ask the mods on plurk or the discord channel.
Daeva: The beauties and seducers of vampire society. Why hunt for prey when you're so lovely that you can make it come to you? Social manipulators and incarnations of want, they're masters at making mortals dance to their tune, but in exchange, they're far more obsessed with mortals than the other clans. Good luck in prying the Daeva away from their toys for anything less than a complete societal breakdown, because they just aren't having it. Their supernatural talents lean towards Celerity (speed) and Vigor (strength), and their clan specialty is Majesty, putting the supernatural into your wow factor to get what you want.
Gangrel: The tough guys, almost animalistic in their ferocity, exemplifying all the predator that a vampire can be. There's no doubt in the mind of a Gangrel, no complex emotional wrestling with the Beast. See something you want? Go take it before someone else gets it. But a Gangrel who is too confident in themselves will quickly learn the truth of 'there's always something bigger.' Truly successful Gangrels are survivors first, and screw anybody else. Their supernatural talents lean towards Animalism (the manipulation of animals) and Resilience (stamina and survival), and their clan specialty is Protean, the ability to change their shape.
Mekhet: Now you see me, now you don't. Let the other clans throw themselves around with power, attraction, fear - the Mekhet will be there and gone again before the others can grab a bite of anything. They move through the shadows, gathering blood and knowledge, and they get everywhere. No secret or vein is safe, but they lose a little something of themselves along the hunt, and react more strongly to the weaknesses of sun, fire, and torpor. Their supernatural talents lean towards Celerity (speed) and Obfuscate (hiding), and their clan specialty is Auspex, enhancing their senses (including supernatural ones) with the power they draw from blood.
Nosferatu: You want creepy? You got it. Here's something that fell out of a horror movie and doesn't want to go back. The Nosferatu are feared even among their own kind, nevermind the mundane humans they prey upon. No matter who you are, something in your gut tells you that they're not quite right. No one wants to be around something like that, not even other creeps and horrors. Their supernatural talents lean towards Obfuscate (hiding) and Vigor (strength), and their clan specialty is Nightmare, the manipulation of fear.
Ventrue: The kings of the night. A Ventrue tells you what they want done, and you somehow find yourself doing it. They glory in the political games of vampire society; they plot, they move, they win. Ventrue are always winners, and they're coming to take their prize. Getting to the top is easy. Staying there, when everyone else wants that spot? Not so much. And if a rival doesn't do the Ventrue in, all the people they're stepping on in their climb might take things into their own hands. Their supernatural talents lean towards Animalism (the manipulation of animals) and Resilience, and their clan specialty is Dominate, using the weight of their supernatural talent to impose their will on others, regardless of what the person actually wants.
The Carthian Movement: Bold revolutionaries of the night. The Carthians want revolution; exactly what that revolution entails varies from Kindred to Kindred. Most Carthians are the younger side - less than a century old - and not at all pleased by the typical vampire society that gives power to the oldest and strongest. They want democracy for the dead. And they're ready to fight for it at the drop of a hat, with as much violence is called for to achieve their goals. The Carthian movement is not nice protestors with signs and songs of solidarity. They're bombs thrown into windows and attack dogs. Watch out.
The Circle of the Crone: Your Mother sent you out into the night, and you feasted. The Circle is home to the wild, spiritual parts of Kindred society - think New-Age hippies going back to nature, except with violence and blood instead of flowers and candles. Chanting's still a thing, though. They don't have a single set of beliefs, but use the banner as a catchall for a massive number of smaller sects. They do, however, keep secret among themselves the blood sorceries called Crúac, rituals that spread quickly through the many communication lines the Circle keeps open. If the wild of your nature appeals to you, this is your home and kin - other Kindred would do well to stay away.
The Invictus: The old powers of the night. Invictus are organized hierarchy, almost feudal nobility; everyone knows exactly where they stand. And, of course, everyone is scheming and playing politics to stand a little higher. In some ways the 'default' of vampire society, they are the origin and keepers of the Masquerade. The Invictus are the ones who write Kindred history, and they offer a chance to be a part of that history. Eventually, as long as you play your role and don't shake things up too badly.
The Lancea et Sanctum: The church of the damned. By being dead, Kindred have given up God's blessing, but they can still do His will. Like wolves who pick at the edges of a flock of sheep to drive them away from cliffsides, and they pick upon mortal church-goers in much the same way. Tests of faith weed out the weak, and those who fail to measure become the next in the line of the damned. They are the moral center of vampire society the same way Invictus is the secular hierarchy - or so they like to portray themselves. They keep to themselves Theban Sorcery, "dark miracles" given only to the highest within the church.
The Ordo Dracul: The Order of the Dragon, the twisted scientists of the Kindred condition. They study and experiment - to become better vampires, or to become human again, or for a thousand other reasons. They seek out truth, both in the histories and in the current reality of the Kindred, and they care relatively litle for politics. And there is definitely something to what they're doing - their secret rituals, called the Coils of the Dragon, allow them to manipulate their vampiric condition to a far greater extent than any other vampire. And in their endless quest for knowledge, they are the covenant most likely to trip and discover the other kinds of supernatural beings.
VII: This covenant, if it can be called that, is not acknowledged by the others. Politics and sunlight aren't the only dangers to a vampire's unlife - there's also these guys, vampires who murder other vampires. They seem to have some connection to the Strix, but beyond that, little to nothing is known of them.
The bite and Vitae: The signature of the vampire; biting people in order to drain their blood. Kindred call it the Kiss, and for good reason - it is exquisite pleasure, bound up with sex and the dark. For the mortal bitten, it may as well be, and it can grow addictive quickly, even if their memories of it are fuzzy. For the vampire, the sated feeling does not last long past when they lick the wounds closed and abandon their prey. A certain amount of fresh blood is consumed every night when the Kindred rise - thus, they are always hungry. This living blood - called Vitae - also fuels many of their supernatural abilities. A vampire that is using more powers of the night gets hungry much faster.
The Blood Bond: Also called Vinculum, the blood bond is a powerful, onesided emotion that exists as a result of drinking a vampire's Vitae. It is most commonly used to bind ghouls, and to bind new vampires to their sires, but can be used for any number of other purposes. It isn't love so much as it is a combination of attraction and obsession. The thrall wants their master's approval more than anything. A complete bond prevents other blood bonds from forming, and all bonds last a year from the most recent taste of blood.
Healing and weapon resistance: Vampires don't get hurt in the same way that humans do. You shoot them, they laugh, they kill you. And then they suck your blood to heal their wounds. Aside from sunlight and fire, only a few rare supernatural things deal truly lasting harm to vampires. Bruises and broken bones won't stop a corpse. However, it does come with a bit of a downside - vampire bodies naturally attempt to return to the state in which they were Embraced, including length of hair and fingernails. Hope you didn't use any expensive hair dye.
Amaranth: Vampire cannibalism. Also called diablerie, this is the most dangerous and forbidden act of the vampire, for it is not the mere taking of blood. It is the consumption of the soul, personality and memories of the victim bleeding into the perpetrator, changing them forever. The ghost of the one you ate doesn't go away, and no matter how much power you gain from it - and the gains have the potential to be great - it marks you. And those marks can be seen by someone who knows where to look.
Disciplines & Devotions: The unique abilities of vampires, the individual abilities that set vampires apart from each other. They include physical enhancements, manipulation of the minds of others, and sensory abilities, among other things. You can find an index of Disciplines under powers here. A Discipline is a series of abilities that must be developed; a Devotion is a single ability.
Sunlight: On the skin of young vampires, it blisters and burns. On the older, it is even more dangerous, a genuine risk of fire. Even aside from that, the Kindred feel a compulsion to sleep through the light of day; staying awake past dawn is harder for them than it is for a college student after an all-nighter on their final paper. Shelter from the sun is a critical need for vampires, and when the sun approaches, they will do anything to get it.
Fire: Vampires touched by flame go up like they're made of tinder, and the burns don't heal instantly in the way that other injuries do. For this reason, fire is a major weapon of any would-be vampire hunters.
Staking: A wooden stake through the heart puts a vampire down. Not for keeps, though - a stake through the heart only causes a vampire to go into torpor, making them truly dead to the world. Of course, it's all too easy to just leave them for the sun to reach after that.
Frenzy: Vampires carry around with them a predatory aura - and when they meet each other, it's all too likely for sparks to fly. This aura can trigger a fight or flight response in other Kindred, a madness known as frenzy that ends either in one party fleeing blindly in fear or the two fighting like rabid animals. Other things - including fear of sunlight and fire, hunger and bloodlust, and the auras of other supernaturals - can also induce frenzy.
What goes in: While vampires cannot keep down normal food and drink, they are affected by whatever is in the blood they consume. Drinking from a drunkard will pass on the alcohol, and the same is true of any number of drugs, both human and supernatural. The blood of certain other supernaturals also has an effect - changeling blood, for example, will leave any vampire drinker quite thoroughly stoned.
Losing touch: While not a physical weakness, vampires do not do well without something to ground them in remembered humanity. They often have something that keeps them connected, whether it's writing emails to an old school friend like nothing has changed or stalking around their old apartment complex in a fit of nostalgia. Vampires defend these things fiercely - because they know that losing them is losing just a little more of what makes them human.
Age and Torpor: As a vampire grows in power - which usually correlates to age, though it is possible to quickly gain potency by other methods - they require more potent blood to sustain themselves. Young Kindred can subsist on animals without even biting the flesh of a human; the oldest Kindred require the blood of their fellows to wake again each night. In order to lower these requirements, a vampire can voluntarily enter a state called torpor, the sleep of the dead, in which they appear to be truly a corpse. Those who enter torpor will awaken after decades or centuries of strange, muddy dreams.
Humans who have ingested the blood of vampires, and thus are bound to the one who feeds them, addicted to that blood. They're a little better than mortal, a little stronger and a little tougher, and they do not age. In vampire society, they're treated as a middle ground between humans and Kindred, and being a ghoul is often the first step to becoming a proper vampire.
For many vampires, at least one good ghoul is a necessity. Someone needs to be around in case the landlord drops by in the middle of the afternoon. Fortunately, they're easy to keep loyal with the use of the blood bond; as ghouls must be fed once a month to keep their abilities, there's next to no chance of it running out.
Humans aren't the only things that can be made into ghouls - animals can be fed the blood of vampires as well, and receive similar benefits.
Dark creatures like owls made of smoke, the Strix are the enemies of the Kindred. They can't be called dead, as they were never alive at all, but like vampires, they persist by stealing life from the living, taking the same vital energies in the form of breath instead of blood. Chased away by sun and fire, they have some manner of connection to the Kindred.
And they're not happy that the Kindred deny that kinship at every turn. Nor are they exactly happy that the Kindred can experience the pleasures of flesh while they cannot - at least, not without stealing the body of something dead to do it with. Needless to say, the Kindred are by far their favored victims, stronger, faster, and less prone to decay than a mere normal corpse.
Most Strix are slow planners and infiltrators of Kindred communities, and because few know the ways to identify them, the mere rumour of the Owls can be as destructive to a group of Kindred as the actual presence of one. The two main signs are a flash of yellow in the eyes, or the fact that a Kindred possessed will not burn in sunlight, their own essence buried beneath that of the Owl safely hidden from the sun in their flesh.