I hadn't grown fangs. I'd been expecting them to sprout and had been checking my teeth in the mirror every night for three weeks before Mr. Crepsley caught me.

"What are you doing?" he asked.

"Looking for fangs," I told him.

He stared at me for a few seconds, then burst out laughing. "We do not grow fangs, you idiot!" he roared.

"But… how do we bite people?" I asked, confused.

"We do not," he told me, still laughing. "We cut them with our nails and suck the blood out. We only use our teeth in emergencies."

"So I won't grow fangs?"

"No. Your teeth will be harder than any human's, and you will be able to bite through skin and bone if you wish, but it is messy. Only stupid vampires use their teeth. And stupid vampires tend not to last very long. They get hunted down and killed."

I was a little disappointed to hear that. It was one of the things I liked most about those old vampire movies: The vampires looked so cool when they bared their fangs.

But after some thought, I decided I was better off without the fangs. The fingernails making holes in my clothes were bad enough. I would have been in real trouble if my teeth had grown and I'd started cutting chunks out of my cheeks as well!

Most of the old vampire stories were untrue. We couldn't change shape or fly. Crosses and holy water didn't hurt us. All garlic did was give us bad breath. Our reflections could be seen in mirrors, and we cast shadows.

Some of the myths were true, though. A vampire couldn't be photographed or filmed with a video camera. There's something odd about vampire atoms, which means all that comes out on film is a dark blur. I could still be photographed, but you wouldn't get a clear photo of me, no matter how good the light.

Vampires were friendly with rats and bats. We couldn't turn into them, as some books and films said, but they liked us — they knew from the smell of our blood that we were different from humans — and often cuddled up to us while we were sleeping, or came around looking for scraps of food.

Dogs and cats, for some reason, hated us.

Sunlight would kill a vampire, but not quickly. A vampire could walk around during the day, if he wrapped up in lots of clothes. He'd tan really fast and start to go red within fifteen minutes. Four or five hours of sunlight would kill him.

A stake through the heart would kill us, of course, but so would a bullet or a knife or electricity. We could drown or be crushed to death or catch certain diseases. We were tougher to kill than normal people, but we weren't indestructible.

There was more I had to learn. A lot more. Mr. Crepsley said it would be years before I knew everything and was able to function by myself. He said a half-vampire who didn't know what he was doing would be dead within a couple of months, so I had to stick to him like glue, even if I didn't want to.

When I finished my bagel, I sat and bit my nails for a few hours. There wasn't anything good on TV, but I didn't want to go outside, not without Mr. Crepsley. We were in a small town, and people made me nervous. I kept expecting them to see through me, to know what I was and to come after me with stakes.

When night came, Mr. Crepsley emerged and rubbed his belly. "I am starving," he said. "I know it is early, but let us head out now. I should have taken more of that silly Scout-man's blood. I think I will track down another human." He looked at me with one eyebrow raised. "Maybe you will join me this time."

"Maybe," I said, though I knew I wouldn't. It was the one thing I'd sworn I would never do. I might have to drink the blood of animals to stay alive, but I would never feast on one of my own kind, no matter what Mr. Crepsley said, or how much my belly growled. I was half vampire, yes, but I was also half human, and the thought of attacking a living person filled me with horror and disgust.

Blood…

Mr. Crepsley spent a lot of his time teaching me about blood. It's vital to vampires. Without it we grow weak and old and die. Blood keeps us young. Vampires age at a tenth the human rate (for every ten years that pass vampires only age one), but without human blood, we age even quicker than humans, maybe twenty or thirty years within a year or two. As a half-vampire, who aged at a fifth the human rate, I didn't have to drink as much human blood as Mr. Crepsley — but I would have to drink some to live.

The blood of animals — dogs, cows, sheep — keeps vampires going, but there are some animals they — we — can't drink from: cats, for instance. If a vampire drinks a cat's blood, he might as well pour poison down his throat. We also can't drink from monkeys, frogs, most fish, or snakes.

Mr. Crepsley hadn't told me the names of all the dangerous animals. There were a whole lot, and it would take time to learn them all. His advice was to always ask before I tried something new.

Vampires have to feed on humans about once a month. Most feast once a week. That way, they don't have to suck much blood. If you only feed once a month, you have to drink a lot of blood at one time.

Mr. Crepsley said it was dangerous to go too long without drinking. He said the thirst could make you drink more than you meant to, and then you were probably going to end up killing the person you drank from.

"A vampire who feasts frequently can control himself," he said. "One who drinks only when he must will end up sucking wildly. The hunger inside us must be fed to be controlled."

Fresh blood was the best. If you drink from a living human, the blood is full of goodness and you don't need to take very much. But blood begins to go sour when a person dies. If you drink from a dead body, you have to drink a lot more.

"The general rule is, never drink from a person who has been dead more than a day," Mr. Crepsley explained.

"How will I know how long a person's been dead?" I asked.

"The taste of the blood," he said. "You will learn to tell good blood from bad. Bad blood is like sour milk, only worse."

"Is drinking bad blood dangerous?" I asked.

"Yes. It will sicken you, maybe turn you crazy or even kill you."

Brrrr!

We could bottle fresh blood and keep it for as long as we liked, for use in emergencies. Mr. Crepsley had a few bottles of blood stored in his cloak. He sometimes had one with a meal, as if it were a small bottle of wine.

"Could you survive on bottled blood alone?" I asked one night.

"For a while," he said. "But not in the long run."

"How do you bottle it?" I asked, examining one of the glass bottles. It was like a test tube, only the glass was darker and thicker.

"It is tricky," he said. "I will show you how it is done, the next time I am filling up."

Blood…

It was what I needed most, but also what I feared most. If I drank a human's blood, there was no going back. I'd be a vampire for life. If I avoided it, I might become a human again. Maybe the vampire blood in my veins would wear out. Maybe I wouldn't die. Maybe only the vampire in me would die, and then I could go home to my family and friends.

It wasn't much of a hope — Mr. Crepsley had said it was impossible to become human again — but it was the only dream I had to hold on to.