Margot met Robert on a Wednesday night toward the end of her fall semester. She was working behind the concession stand at the artsy movie theatre downtown when he came in and bought a large popcorn and a box of Red Vines.

“That’s an … unusual choice,” she said. “I don’t think I’ve ever actually sold a box of Red Vines before.”

Flirting with her customers was a habit she’d picked up back when she worked as a barista, and it helped with tips. She didn’t earn tips at the movie theatre, but the job was boring otherwise, and she did think that Robert was cute. Not so cute that she would have, say, gone up to him at a party, but cute enough that she could have drummed up an imaginary crush on him if he’d sat across from her during a dull class—though she was pretty sure that he was out of college, in his mid-twenties at least. He was tall, which she liked, and she could see the edge of a tattoo peeking out from beneath the rolled-up sleeve of his shirt. But he was on the heavy side, his beard was a little too long, and his shoulders slumped forward slightly, as though he were protecting something.

Robert did not pick up on her flirtation. Or, if he did, he showed it only by stepping back, as though to make her lean toward him, try a little harder. “Well,” he said. “O.K., then.” He pocketed his change.

But the next week he came into the movie theatre again, and bought another box of Red Vines. “You’re getting better at your job,” he told her. “You managed not to insult me this time.”

She shrugged. “I’m up for a promotion, so,” she said.

After the movie, he came back to her. “Concession-stand girl, give me your phone number,” he said, and, surprising herself, she did.

From that small exchange about Red Vines, over the next several weeks they built up an elaborate scaffolding of jokes via text, riffs that unfolded and shifted so quickly that she sometimes had a hard time keeping up. He was very clever, and she found that she had to work to impress him. Soon she noticed that when she texted him he usually texted her back right away, but if she took more than a few hours to respond his next message would always be short and wouldn’t include a question, so it was up to her to reinitiate the conversation, which she always did. A few times, she got distracted for a day or so and wondered if the exchange would die out altogether, but then she’d think of something funny to tell him or she’d see a picture on the Internet that was relevant to their conversation, and they’d start up again. She still didn’t know much about him, because they never talked about anything personal, but when they landed two or three good jokes in a row there was a kind of exhilaration to it, as if they were dancing.

No, I’m serious, stop fooling around and come now,