“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.”

“I . . . Why do you want me to?” There was a flicker of something in Greta’s look. I couldn’t tell whether it was a flicker of love or regret or meanness, and then she said, “Why wouldn’t I want you to?” Because you hate me, I thought, but I didn’t say it.”

“Because maybe I don't want to leave the planet invisible. Maybe I need at least one person to remember something about me.”

“The day my mother gave us the keys, she also made me and Greta sign a form so that the bank knew our signatures. To get in we had to show our key and sign something so they would know it was really us. I was worried that my signature wouldn't look the same. I wasn't sure when that thing would happen that made it so you always signed your name exactly the same, but it hadn't happened to me yet. So far I'd only had to sign something three times. Once for a code of conduct for the eighth grade field trip to Philadelphia, once for a pact I made with Beans and Frances Wykoski in fifth grade that we'd never have boyfriends until high school. (Of the three of us, I'm the only one who kept that pact.)”

“Greta knows that for me there are no good parties. I’m okay with one or two people, but more than that and I turn into a naked mole rat. That’s what being shy feels like. Like my skin is too thin, the light too bright. Like the best place I could possibly be is in a tunnel far under the cool, dark earth. Someone asks me a question and I stare at them, empty-faced, my brain jammed up with how hard I’m trying to find something interesting to say. And in the end, all I can do is nod or shrug, because the light of their eyes looking at me, waiting for me, is just too much to take. And then it’s over and there’s one more person in the world who thinks I’m a complete and total waste of space.”

“Nothing had changed. I was the stupid one again. I was the girl who never understood who she was to people.”