The weak-willed student Yamada was helping his homeroom teacher, Mayumi, move materials into the storage room when suddenly the door closed and they were trapped inside. Unable to move in the cramped space, they remained pressed together for a long time, and as fatigue and breathlessness set in, their minds began to wander into lewd thoughts. Later, miraculously freed, the two found themselves in trouble again as Yamada had broken his promise with some delinquents. To escape them, he and Mayumi once more hid under the bed in the nurse's office…
