“I stared at Greta’s back. At her matted hair, decorated with brown torn leaves and dirt. What was happening to my sister? What if I’d never come? How long would she have stayed hidden in those cool, damp leaves? How long before she woke up alone and scared, with nothing but the howling of wolves to keep her company?”

“Then we left, just me running with my sister, the wolves at our backs.”

“For a long time, all the way through to the end of elementary school, Beans was my only friend. Because that’s how I’ve always been. I only need one good friend to see me through. Most people aren’t like that. Most people are always looking out for more people to know. In the end, Beans was like most people. After a while she had dozens of friends, and by fifth grade it was pretty obvious that even though she was my best friend, I wasn’t hers.”

“As the elevator door started to close, she stood and put up one hand to wave goodbye. That’s one of those frozen memories for me, because there was something in Greta’s solemn wave that made me understand it was about something bigger. That as the elevator door eclipsed the look between us, we were really saying goodbye to the girls we used to be. Girls who knew how to play invisible mermaids, who could run through dark aisles, pretending to save the world.”

“I came to a sketch where the space between my arm and Greta’s arm, the shape of the place between us, had been darkened in. The negative space. That’s what Finn called it. He was always trying to get me to understand negative space. And I did. I could understand what he was saying, but it didn’t come naturally to me. I had to be reminded to look for it. To see the stuff that’s there but not there. In this sketch, Finn had colored in the negative space, and I saw that it made a shape that looked like a dog’s head. Or, no—of course, it was a wolf’s head, tilted up, mouth open and howling. It wasn’t obvious or anything. Negative space was kind of like constellations. The kind of thing that had to be brought to your attention. But the way Finn did it was so skillful. It was all in the way Greta’s sleeve draped and the way my shoulder angled in. So perfect. It was almost painful to look at that negative space, because it was so smart. So exactly the kind of thing Finn would think of. I touched my finger to the rough pencil lines, and I wished I could let Finn know that I saw what he’d done. That I knew he’d put that secret animal right between Greta and me.”

“It was a nice thing for her to say. In her way. With Greta you have to look out for the nice things buried in the rest of her mean stuff. Greta’s talk is like a geode. Ugly as anything on the outside and for the most part the same on the inside, but every once in a while there’s something that shines through.”

“The walls of the tunnels were covered with so much dirt, it was almost like fur. I thought those tunnels were the kind of places wolves might live. I thought they were like the vessels of the human heart.”