“It’s a communication system,” said Kira. It was early evening, and since she’d skipped lunch she’d decided to join Marcus for an early dinner. He’d brought sushi from a street vendor, and they were eating together in an empty room on the third floor, away from all the bustle and people below. She took a bit of sushi, swallowed it, and kept talking, so eager she could barely keep up with herself. Her conversation with Samm still burned in the back of her mind, glowing banks of hot emotional coals, but she forced herself to ignore them. “A chemical communication system, like with ants, but a zillion times more complicated. Imagine being able to talk to people just by breathing—you wouldn’t have to say a word, you’d just know everything—”

“I can’t imagine you not saying a word,” said Marcus. “I think you’d go crazy first.”

“Ha-ha,” said Kira, rolling her eyes.

“So, how does it work, then?”

“Well, I don’t know what kinds of things they can say chemically—I catalogued at least twenty separate pheromones, but even at ten times that amount it would be an incredibly small vocabulary—but if, say, one of them was ‘I’m wounded,’ as soon as one soldier got wounded, all the others would instantly know about it, and they’d have a pretty good idea of where to find him. It’s a sense we don’t even have, like a social sense, and to him it’s constant and second nature. Can you imagine what it would be like to be cut off from that? He must feel more alone than…” She thought again about what he had said, calling humanity his parents; what was it like out there, the vast expanse of America lying empty and silent? “They’re alone, Marcus. That’s kind of tragic, don’t you think?”

“Good thing he has you to look out for him, then,” said Marcus. “I’d hate for the poor Partial to feel lonely.”

“That’s not what I meant,” said Kira. “This is what I love to do, Marcus—you’re a medic too, I thought you’d understand why this is so cool. It’s not about Samm, it’s about—”

“Ah, so now you guys are on a first name basis, huh?” He tried to play it off like he was joking, but Kira could feel real emotion beneath it. She knew him too well. “I’m kidding, Kira. But seriously, he’s a Partial. Mankind’s greatest enemy, remember?”

“That’s what I’ve been trying to tell you. I don’t know that they are anymore.”