Rio is a newly appointed teacher struggling to keep her collapsing class under control. During a meeting, the delinquent students promise to attend lessons if she shows them her breasts. Desperate to save the class, she agrees—but they immediately push further, grabbing her huge tits and gang-raping her one after another until she is reduced to serving every male student. She regrets believing it would happen only once, but by then it is too late. All student characters and performers are adults.