After school in the classroom, Rin calls out the student teacher who has come for training practice. Handing him a letter, she teases him with the expectation of a love confession—only for the note to read, "Are you still a virgin, teacher?" That single line shatters his solemn expression, quickly replaced by a sly grin as she tempts him into masturbating. A mischievous student demanding service, and a virgin teacher utterly defeated by her seduction—their master-servant relationship begins here.