Female teacher Masami gets caught up in a prank by male students, forced to ingest a diuretic, and is suddenly overwhelmed by an intense urge to urinate during class. Desperately trying to reach the bathroom while secretly leaking, she heads to the restroom only to find another trap waiting—she's forced to relieve herself in the boys' toilet. The male students witness the scene, and Masami gradually transforms into a sexual object for their amusement. As she succumbs to the pleasure of incontinence, the story depicts her mind and body drowning in the sensation, completely entranced by the euphoric experience.