My girlfriend and I are browsing in a quiet, dusty bookstore. I’ve settled into a worn armchair tucked between towering shelves, while she stands a few feet away, completely absorbed in a book with her back to me.

The silence is peaceful at first, but as the minutes stretch, a wave of sleepiness and boredom washes over me. Waiting is never my strong suit. I pull my phone from my pocket, the screen bright in the dim literary light, and with a few taps, I launch a specific, familiar app.

A moment later, the distinct, low buzz vibrates through the quiet air. It’s followed immediately by her soft, startled gasp.

Hearing it, my lips curl into a slow, knowing smile. I don’t look up from my phone.