A few other passengers sit scattered throughout the car—students, by the look of their uniforms—but none of them pay much attention to the strange scene unfolding near the back.

His arm hooks over the back of her seat, fingers dangling lazily near her shoulder. He doesn't look at her. He stares ahead, watching the dark tunnels swallow the light every few seconds, a half-smile tugging at the corner of his mouth.

His hand drops from the seat back to her shoulder, thumb brushing against the collar of her jacket once, casual, before his fingers curl into the fabric and tug her just slightly closer.