A shy but insatiable woman named Nonomiya enjoys masturbating even when she's just relaxing at home. One day while playing with herself, she becomes nervous that her mother might catch her and starts sweating. She decides to explore her excitement further by exposing herself naked at school during breaks or masturbating openly in classrooms. One night, she finds herself alone in a classroom wearing nothing but her underwear when another student enters looking to steal some girl's gym clothes. Both girls are now vulnerable due to their secrets being exposed, so they decide to wander around the empty school late at night, completely nude...and have wild, unprotected sex!