My school life is almost over, and the beloved Ms. Nobuko Terabayashi has finally become my homeroom teacher. She's the most popular teacher on campus—kind, beautiful, and my ideal woman. Lately, however, my grades have been slipping, and the reason is unexpected. Her chest is always so exposed that I can't concentrate on studying. Just seeing her bra makes my heart race, but when her nipples become visible, I completely lose control. In this state, she grows concerned about my performance and arranges private after-school tutoring—just the two of us. What unfolds between us will pull me in far deeper than I ever imagined.