The Shadowhunter's Codex by Cassandra Clare, Joshua Lewis

dangerous: the encanto , or “fascination . ” Vampires can, with simple prolonged eye contact, convince mundanes and even Shadowhunters of almost anything, and can persuade them into almost any act. This is a skill that must be developed and practiced by vampires, and so it is typically the older and more powerful vampires that make use of it. If you live in an area particularly rife with vampire activity, you should consult your local Institute about prioritizing training to resist the encanto .
    My first album will be titled One Foot in Hell Already
    I hereby deem that title “Totally Stupid.”
    You love that title! You cannot resist the encanto !
VAMPIRES AND THE LAW
Many new Shadowhunters are surprised to learn that it is not against the Law for a vampire to drink blood from a human, provided that the human remains alive. This is because of the healing properties of vampire saliva. When a vampire drinks from a victim, it increases the red blood cell count in that victim, making them stronger, healthier, and able to live longer. The effect is small, but it mitigates the weakening effect of losing blood, and so a bitten human usually remains unharmed.
Nevertheless, the risk of accidentally killing a human by drinking from him too deeply, and the general sense of menace around having one’s blood drained, have led most “civilized” vampires to eschew drinking from living human victims (other than subjugates ) in favor of pre-drawn blood or the blood of animals. By the Accords, vampires must abide by the same mundane laws against murder as any other Downworlders, but vampires are the only Downworlders who might commit murder for food, potentially for survival. It is notable, and admirable, that so many vampires have voluntarily committed themselves to the same respect for human life as the other signers of the Accords.
    Now Simon is angry too. He and Luke are both pacing around yelling at nobody about the Codex. Summary: “Only vampires murder for food? That is rich.” It’s hard being the Monster Manual.
VAMPIRE POLITICS
Like werewolves, vampires consider themselves to be on some level brethren with all other vampires, no matter what clan they are affiliated with. A vampire who raised a hand against another, except in the rare circumstance of a clan war, would be considered anathema by the vampire community, and his life would be forfeit. The Nephilim generally stay out of these matters of internal justice, although we will sometimes intervene to arbitrate conflicts between clans to stave off full-out battle. When clan wars do occur, leadership changes, as it does with werewolves: Whoever kills the head of a vampire clan becomes its leader.
Among Downworlders only faeries are more committed to notions of honor and etiquette than vampires. Vampires are often found making oaths and vows, which they take very seriously. These vows are usually written and signed in blood—not a surprise, given the vampire obsession with blood generally. These blood-oaths are binding: Vampires are compelled by the oaths’ contents and cannot violate them unless the bond is broken through further, and more onerous, ritual. A vampire who has thus sworn an oath to you under these circumstances can be trusted to follow at least the letter of the oath in the strictest detail. Conversely, you should be suspicious of a vampire who is willing to make a promise to you but will not swear to that promise in blood.
    I wish Simon would vow to return my Ghibli DVDs.
    I so vow! In blooooooood?
    Never mind!
WEAKNESSES
Obviously it would be the preference of all Nephilim to never be forced to bring harm to a vampire, but history teaches us that it is wise to know how to defend oneself against them, and what their strengths and weaknesses might entail. The Accords require that vampires turn away from their natures as hunters and predators, just as humans must choose to turn away from our own abilities to kill and harm.
Vampires are extremely