He's an ordinary, dull male student. He's never had a girlfriend, and of course he's a virgin. One day, he gets molested by a pervert on a crowded train, and when he goes to school with a pounding heart, the class is buzzing with talk of a new teacher. "I wonder if I'll see him again..." The new teacher who appears before him while he's still dreaming is the lewd older sister who molested him on the train!