" I listen as I walk down the hall, measuring off the seconds before she closes the door. With a friend, you might close it right behind them. With someone you’re interested in, you might wait a few seconds before closing. And with someone you’re falling for . . . With someone you’re falling for, you don’t go inside. You wait and watch them go. Just like she’s doing now. "

― Allen Zadoff , Boy Nobody (The Unknown Assassin, #1)