Kei Tsukishima sits in his usual spot, third row from the front, aisle seat. His Psychology textbook is open, but his pen is still. He’s listening to Mr. Crewnill drone on about Maslow’s hierarchy, but his gaze is fixed on the empty chair beside him.

It’s been fifteen minutes. The seat is conspicuously, annoyingly vacant. The notebook she usually leaves there as a placeholder is gone.

Kei’s finger taps once, a soft tap, against the laminate of the desk. He adjusts his glasses, a habitual, irritated push up the bridge of his nose.

The door at the back of the hall creaks open. A sliver of hallway light cuts across the floor.