It rained on the night Kit Sterling decided to stop caring.

She was fifteen then, a freshman with a backpack too heavy and ambitions too light to be properly measured. She stood in the parking lot of a house she barely knew, rain flattening her hair against her cheeks, watching headlights carve through the dark as car after car pulled away. Julian Vane had not come out.

She waited twenty minutes because that was how long it took for the humiliation to fully arrive-not a quick, hot flush, but a slow, cold settling that seeps under the skin and stays. She had done exactly what he'd asked. She had gone to the party. She had worn the dress. She had let it happen-the thing she hadn't meant to let happen-because everyone else seemed to think it was fine, and she had not, then, trusted her own sense of what was fine.

The front door of the house opened. Light spilled out. She looked up, but it was not Julian. It was two of his friends, laughing about something, oblivious to the girl in the parking lot who had been soaked through. They got into a truck and drove away. The door closed. The light was gone.

Kit pulled out her phone. No messages. She looked at the last thing Julian had sent her three days ago: a string of emojis that had seemed, at the time, to mean something. She saw now that they meant nothing; they were the linguistic equivalent of a shoulder shrug.

She walked home. It was four miles, and she walked all of it. Somewhere around the second mile, in the stretch between a closed laundromat and a gas station that smelled like old coffee, something in her chest changed texture. It didn't break-that is a word she would have rejected as too melodramatic. It did something more subtle and more permanent.

It hardened. Never again, she told herself, the rain collecting in her eyelashes. Never again for someone else's sake. Never again because everyone else was doing it, or because a boy asked nicely, or because she wanted to be the kind of girl who said "yes" to things.

She meant it. She meant it for a year.

She did not know, that night, about Jax Thorne. She did not know about her sister Maya's plans, or her father Arthur's rule, or the fact that someone was going to show up at her school with a guitar and make everything she'd decided about herself suddenly feel negotiable. She did not know about Leo Vance, either-the new boy who would arrive in October rain, smitten and hopeful, and whose own clumsy love story would somehow become the hinge on which her life swung open.

But that is the thing about the rules we make for ourselves in parking lots in the dark. They feel permanent. They feel like architecture.

Sometimes they are only walls. And sometimes, someone knocks.