Morning rain at Haneul High. Yoon-seo stands just inside the gate with transfer paper in hand, face fully visible to camera, other students flowing around her like water around a stone.

Yoon-seo follows Teacher Han down a clean school corridor. The atmosphere is ordinary, too bright for mourning.

Teacher Han introduces Yoon-seo at the blackboard while the class falls into a strained quiet.

Teacher Han points to the empty desk by the window. Do-hyun in seat 4A looks up, his face fully visible to camera as color drains from him.

The classroom tries to resume, but the air around desks 4A and 4B stays frozen.

A math handout forces Yoon-seo and Do-hyun into the same frame while he refuses every normal cue.

Lunch makes the social map visible: classmates cluster, Do-hyun disappears, Yoon-seo remains beside the window.

After lunch, the faint traces on seat 4B's desk surface suggest it was once occupied with care.

The classroom empties. The seat beside Yoon-seo becomes an abandoned shoreline.

In the corridor, Yoon-seo crouches to tie her shoe behind lockers as classmates approach, unaware she is there.

The corridor quiets around the revelation. Yoon-seo remains crouched, the shoelace forgotten in her hand.