“Um, this girl called Freddie,” Lace whispered.

“She at home?”

Lace shrugged.

“Well, let’s hope not.” I jumped up onto the rail and across.

“Jesus, dude!” Lace squeaked.

I turned back to look down through the two-and-a-half-foot gap, realizing I should at least pretend to show fear, if only for Lace’s sake. The parasite doesn’t want its peeps too cautious; it wants us picking fights, complete with the biting and the scratching and other disease-spreading activities. We carriers don’t mind a little danger.

Lace, though, was fully human, and her eyes widened farther as she stared down.

“Come on,” I whispered soothingly. “It’s just a couple of feet.”

She glared at me. “A couple of feet across. Seven stories down!”

I sighed and jumped back up, steadied myself with one loot on each rail, and leaned back against the building. “Okay, I’ll swing you across. I promise I won’t drop you.”

“No way, dude!” she said, her panic breaking through the whisper.

I wondered if the cleaner had heard us and was already calling the cops. My Health and Mental badge looked real, and if a policeman called the phone number on the ID, there would be a Night Watch employee sitting at the other end. But Lace had been right about the whole illegal entry thing, and if someone went looking to complain to my boss in person, they would find only a bricked-up doorway in a forgotten basement of City Hall. The Night Watch had cut most of its official ties two hundred years ago; only a few bureaucrats remained who knew the secret histories.

I leaned down and grabbed Lace’s wrist. “Sorry, but…”

“What are you—?” She squealed as I lifted her up and over, setting her down on the next balcony.

When I jumped down beside her, Lace’s face was white.

“You … I could have…” she sputtered. Her mouth was open, and she was breathing hard. On the tiny balcony, my senses started to tangle up with one another, smell and sight and taste, the parasite pushing its advantage. Excitement radiated from Lace; I knew it was only fear making her pupils expand, her heart pound, but my body responded in its own blind way, construing it all as signs of arousal. My hands were itching to take hold of her shoulders and taste her lips.

“Excuse me,” I squeaked, pushing her away from the balcony door.

I knelt and pulled out lock-picking equipment, desperate to get off that balcony and inside, anything to be a few feet farther away from Lace. My fingers fumbled, and I banged my head against the glass on purpose, clearing my brain long enough to squirt the keyhole with graphite.

Seconds later, the door slid open.

I stumbled inside Freddie’s apartment, away from Lace’s smell, sucking in the odors of industrial carpet, recently assembled Ikea furniture, and a musty couch. Anything but jasmine.

When I managed to get back under control, I put my ear to the wall. The welcome roar of a vacuum cleaner rumbled back and forth next door. Taking another deep breath, I collapsed onto the couch. I hadn’t kissed Lace and the cops weren’t on their way—two near disasters averted.

Without catching Lace’s eye, I looked around. Another clone of Morgan’s apartment, the walls innocently white. “Might as well check in here too.”

Lace didn’t say a word, staring at me from where she stood just inside the balcony door. Her expression was still intense, and when I switched on the UV light, the whites of her eyes glowed fiercely. She was rubbing her wrist where I’d grabbed it to lift her across.

She said calmly “How did you do that?”

“Do what?”

“Pick me up. Swing me like a cat.”

I attempted a cavalier smile. “Is that how cats are swung?”

She snarled, revealing a flash of ultraviolet teeth. “Tell me.”

I realized she was still angry and tried to channel Dr. Rat’s lecture voice. “Well, the human body is capable of great strength, you know. Mothers whose babies are in danger have been known to lift cars. And people high on PCP can snap steel handcuffs or even pull their own teeth out with pliers.”

This was a point often made in Hunting 101: Peeps aren’t stronger than normal people in any healthy sense—the parasite just turns them into psychos, setting their muscles at emergency strength, like a car with its gas pedal stuck down. (Which would sort of make carrier peeps controlled psychos, I suppose, though nobody at the Night Watch ever put it like that.)

“So which category do you fall into?” Lace said. “Concerned mother or insane drug addict?”

“Um … more like concerned mother, I guess?”

Lace advanced on me, stuck one stiff forefinger into the center of my chest, her smell overwhelming me as she shouted, “Well, let’s get something straight, Cal. I am not… your… baby!”

She spun on her heel and stomped to the apartment door, unlocking it and yanking it open. She turned back, pulling something from her pocket. For a second, I thought she was going to throw it at me in a wild rage.

But her voice was even. “I found this in Max’s kitchen trash. Guess Morgan never bothered to get her mail forwarded.”

She flicked it at me after all, the envelope spinning like a ninja’s star.

I plucked it from the air and turned it over. It was addressed to Morgan. Just a random piece of junk mail, but now I had a last name.

“Morgan Ryder. Hey, thanks for—”

The door slammed shut. Lace was gone.

I stared after her for a while, the echo of her exit ringing in my exquisite hearing. I could still smell the jasmine fragrance in the air, the scent of her anger, and traces of her skin oil and sweat on my fingers. Her departure had been so sudden, it took a moment to accept it.

It was better this way, of course. I’d been lucky so far. Those moments on the balcony had been too intense and unexpected. It was one thing sitting across a table from Lace in a crowded restaurant, but I couldn’t be alone with her, not in small spaces. I liked her too much, and after six months of celibacy, the parasite was stronger than I was.

And once she thought about my cover story a little more, she’d probably figure I was some kind of thief or con man or just plain freaky. So maybe she’d steer clear of me from now on.

I let out a long, sad sigh, then continued sweeping for bodily fluids.

A long time ago human beings were hairy all over, like monkeys. Nowadays, however, we wear clothes to keep us warm.

How did this switch happen? Did we lose the fur and then decide to invent clothes? Or did we invent clothing and then lose the body hair that we no longer needed?

The answer isn’t in any history books, because writing hadn’t been invented yet when it happened. But fortunately, our little friends the parasites remember. They carry the answer in their genes.

Lice are bloodsuckers that live on people’s heads. So small that you can barely see them, they hide in your hair. Once they’ve infested one person, they spread like a rumor, carrying trench fever, typhus, and relapsing fever. Like most bloodsuckers, lice are unpopular. That’s why the word lousy is generally not a compliment.

You can’t fault lousy loyalty, though. Human lice have been with us for five million years, since our ancestors split off from chimpanzees. That’s a long run together. (The tapeworm, for comparison, has only been inside us for about eight thousand years, a total parasite-come-lately.) At the same time we were evolving away from monkeys, our parasites were evolving from monkey parasites—coming along for the ride.

But I bet that our lice wish they hadn’t bothered. You see, while the chimps stayed hairy, we humans lost most of our body hair. So now human lice have only our hairy heads to hide in. On top of that, they’re always getting poisoned by shampoo and conditioner, which is why lice have become rare in wealthy countries.