Excerpt from The Last Boy and Girl in the World by Siobhan Vivian, plus links to reviews, author biography & more

I remember the first time I met her at a church picnic Morgan had dragged me to when we were in seventh grade. Morgan kept telling me how alike Elise and I were, how much we had in common. I took this as a compliment about our friendship, that if Morgan had to make a new friend, she'd pick the most Keeley person she could find. I pictured Elise as a sweeter, churchier version of me.

And she was, at first glance. Elise was thin and delicate with a brown bob that fell just past her chin and a silver cross pendant that hung in the hollow of her collarbone. I'm not sure if she was surprised that I was coming with Morgan to the picnic, because she'd only saved one extra chair. She stood up and offered both chairs to Morgan and me, and sat in the grass by our feet. I appreciated the show of respect.

But it might have been because Elise was afraid of me. I remember saying all kinds of borderline inappropriate things to her to be funny, like stringing together a bunch of curse words or making dirty jokes or whatever. Morgan kept laughing nervously and telling Elise, "She's kidding, she's kidding," to which Elise quickly forced a smile and replied lightly, "Oh, totally, I knew that."

We were in line for hot dogs when Elise pointed out a boy with flippy hair and mirrored sunglasses playing his guitar to accompany a pastor singing a Jesus song. She leaned in and said to me, "I used to be so hot for that guy, but it turns out he's the absolute worst kisser on the planet." And she stuck out her tongue and rolled it around like someone having a seizure, and then made a gag face. "I can't even see his cuteness anymore. He's, like, tainted."

Neither Morgan nor I had ever French-kissed anyone. We were still playing those pretend games at her house.

"She's not boy crazy or anything," Morgan whispered to me later on the ride home, as if she could read my mind. "She's just . . . uh . . . not shy." And then she threw in, "Like you!" to put me at ease.

Of course, after Elise's dad lost his job and they moved to Aberdeen, I saw plenty of Elise's sweet and churchy side, and I think that's ultimately what I liked best about her, those two identities mashed up together. She was super-sweet with her little brothers, and if we came over when she was babysitting, she'd be playing with them just as much as hanging out with us. And she never talked shit about anyone, even people who completely deserved it, like Wes. Meanwhile, her phone was full of numbers, boys we'd meet at the mall or the movie theater or who went to her church. Elise wasn't so much interested in having a boyfriend as she was in having someone to crush on.

I think, at first anyway, having a boy to obsess about kept Elise from feeling jealous of what Morgan and I had together. Because as close as the three of us were, every so often there were moments where our threesome was eclipsed by the previous twosome. I say this with no offense to Elise, of course. But you can only have one best friend. My friendship with Morgan went all the way to the cradle, because our moms were best friends too. She couldn't compete with that.

Later on, though, when it was both Morgan and Elise getting that kind of attention together, I became the odd girl out.

"Anyway, Jesse and I weren't flirting," I corrected her. "We were joking around."

Again, there is a difference. One I knew all too well.

Morgan cleared her throat. "Keeley, he checked out your butt as you grabbed us bottles of water from the cooler."

I couldn't play off my shock. I spun toward her. "He did not. Shut up."

"He totally did! He watched you walk the entire way!"

I wanted so badly to believe her. And maybe it was the truth. But we'd both heard what her ex-boyfriend Wes had said about me, the kind of girl I was, and I knew Morgan wanted to undo that damage. It was why she broke up with him in the first place. So there was that possibility too. And for me, it was the possibility that seemed more likely.

Excerpted from The Last Boy and Girl in the World by Siobhan Vivian. Copyright © 2016 by Siobhan Vivian. Excerpted by permission of Simon & Schuster Books for Young Readers. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.